Using Myrtus communis extract as a complexion perfector

Abstract

The present invention relates to the cosmetic use of an active ingredient obtained from the species Myrtus communis, as a complexion perfector, by acting on mitochondrial activity. This active ingredient comprises an extract of Myrtus communis, the latter comprising at least 20% carbohydrates and less than 10% polyphenols in the total dry matter of the extract.

Description

Title of the invention: Use of an extract of Myrtus communis as a complexion perfector technical field

[0001] The invention relates to the cosmetic use of an active ingredient obtained from the species Myrtus communis, as a complexion perfector, by acting on mitochondrial activity. This active ingredient comprises an extract of Myrtus communis, the latter comprising at least 20% carbohydrates and less than 10% polyphenols in the total dry matter of the extract. State of the art

[0002] Our modern lifestyle has many consequences for our health and well-being. Our skin is no exception; stress, pollution, lack of sleep, and an unbalanced diet can dull the complexion, leading an ever-increasing number of consumers to seek effective solutions.

[0003] On the other hand, the influence of social media, particularly the omnipresence of photos and videos on social networks, increases consumers' desire for a perfect and radiant complexion. Finally, many consumers are looking for alternatives to heavy makeup and prefer to enhance the natural appearance of their skin.

[0004] This results in a growing need for products that not only improve the appearance of the skin, but also its overall health and contain ingredients of natural origin, perceived as safer and more environmentally friendly.

[0005] In this context, new cosmetic compositions capable of improving the appearance of the complexion, while acting at the cellular and tissue level, in particular by targeting mitochondrial activity, and improving the optical properties of the skin, are particularly sought after in order to meet consumer expectations for innovative products for radiant complexion.

[0006] In this context, the inventor was particularly interested in the plant species Myrtus communis, commonly called myrtle, already known for having cosmetic benefits, in particular as an anti-aging agent, notably for increasing the longevity of skin cells and tissues.

[0007] Thus, it is already known from patent FR 2903601, a cosmetic active ingredient comprising an extract obtained from Myrtus communis capable of increasing the expression of sirtuin 1 (SIRT-1) and reducing collagen glycation, thus making it possible to improve cell longevity and fight against skin aging, such as wrinkles.

[0008] However, the prior art does not disclose the use of such an extract of Myrtus communis for a complexion-perfecting effect. This is the subject of the present invention. Summary of the invention

[0009] Thus, the invention relates to the cosmetic use of an active ingredient obtained from Myrtus communis, for a complexion-perfecting effect. Said active ingredient comprises an extract, said extract being a hydrolysate of Myrtus communis comprising at least 20% carbohydrates and less than 10% polyphenols in the total dry matter of the hydrolysate.

[0010] A complexion-perfecting effect targets its action primarily on the immediate or short-term appearance of the skin by acting specifically on the epidermis, while an anti-aging effect impacts deep and long-term structural changes by acting on the dermis. It follows that an active ingredient can act specifically on the dermis and have no effect on the epidermis. Thus, an active ingredient can have an anti-aging effect and, conversely, not have a complexion-perfecting effect if it does not act on the epidermis. Surprisingly, the inventor fortuitously discovered that the active ingredient of the present invention has an effect on both the dermis and the epidermis, and therefore a complexion-perfecting effect, in addition to the already known anti-aging effect.

[0011] The complexion-perfecting effect refers to a visible and measurable improvement in the overall appearance of facial skin, manifested in particular by a uniformity of skin color, an increase in the brightness and natural radiance of the skin, or an improvement in the reflection and diffusion of light by the skin.

[0012] Preferably, the active principle obtained from the hydrolysate of Myrtus communis is intended to improve the radiance of the complexion by increasing the transmission of light through the stratum comeum, most preferably by decreasing the amount of oxidized proteins in the epidermis.

[0013] The active ingredient according to the present invention thus acts on skin radiance by increasing mitochondrial activity, in particular mitochondrial integrity, mitochondrial dynamics, mitophagy, and ATP production. These beneficial effects on skin radiance, by acting on mitochondrial activity, are biologically reflected at the epidermal level by the increased expression of certain proteins such as aconitase, FHSP27, and sirtuins (SIRT), in particular SIRT3 and SIRT6.

[0014] Indeed, the active principle according to the invention acts on sirtuins 3 and 6 allowing a beneficial action in mitochondrial function, supporting radiance of complexion.

[0015] Sirtuin 3 (SIRT3) and sirtuin 6 (SIRT6) are enzymes belonging to the sirtuin family, which play important roles in various cellular processes. Members of the sirtuin family are distinguished by their diverse cellular localizations and cross-cutting biological functions. Thus, among the seven known enzymes of this family, sirtuins 3 and 6 promote efficient mitochondrial activity. At the cellular level, SIRT3 is localized in the mitochondria, and SIRT6 is primarily located in the nucleus but can translocate to the mitochondria and thereby stimulate SIRT3.

[0016] Furthermore, mitochondria also possess a system for controlling their integrity, which allows them to prevent damage under low stress. This system relies on two essential mitochondrial mediators: aconitase, an enzyme involved in the Krebs cycle and the protection of the mitochondrial genome, and HSP27, a chaperone protein responsible for the integrity of mitochondrial proteins.

[0017] In cases of more significant damage, the dynamic properties of mitochondria can be stimulated, allowing for continuous remodeling through fusion between two mitochondria or fission, generating a healthy mitochondria and a damaged mitochondria, which are then eliminated by mitophagy. In cases of critical damage that could harm the cell, mitochondria are selectively eliminated by mitophagy. These properties support mitochondrial dynamics. By acting on the expression of aconitase and HSP27, the active ingredient of the present invention improves mitochondrial integrity. Mitochondrial dysfunction alters skin quality via free radicals. Indeed, in cases of massive production, these free radicals damage various cellular components, including proteins. Protein oxidation leads to alterations in keratin fibers and the optical properties of the stratum corneum.Thus, improving mitochondrial dynamics is essential to limit the excessive production of free radicals and thereby enhances the radiance of the complexion.

[0018] The active principle of the present invention thus reactivates mitochondrial protective mechanisms. In addition, it advantageously restores ATP (Adenosine triphosphate) production and reduces the level of oxidized proteins.

[0019] According to another preferred object, the hydrolysate is an enzymatic hydrolysate.

[0020] Preferably, the carbohydrates of the hydrolysate are composed mainly of fructose, glucose and galacturonic acid.

[0021] According to another preferred object, the polyphenols of the hydrolysate are ellagitannins, gallotannins, phenolic acids or hydroxybenzoic acids.

[0022] Most preferably, the hydrolysate is obtained by a process comprising the following steps: solubilization of Myrtus communis leaf powder in water acidic environment Enzymatic hydrolysis, separation of soluble and insoluble phases by filtration, centrifugation or decantation, thermal treatment, purification of the soluble fraction, advantageously by absorption on adjuvant, concentration of the active fraction, filtration, and sterilizing filtration.

[0023] Other features and advantages will become apparent from the detailed description of the invention, the examples and figures that will follow. Detailed description of the invention

[0024] Definition

[0025] For the purposes of this invention, "extract of Myrtus communis" means a mixture of at least two molecules obtained from a raw material, namely myrtle, i.e., the species Myrtus communis, regardless of the extraction process used for said molecules. It may, for example, be an extract obtained by aqueous extraction or by hydrolysis.

[0026] By "Myrtus communis hydrolysate" in the sense of the invention, we mean an extract from the plant species Myrtus communis, obtained by a process comprising at least one hydrolysis step with solubilization of the Myrtus communis leaf powder in water, advantageously in an acidic medium, preferably the hydrolysate is an enzymatic hydrolysate.

[0027] For the purposes of this invention, "active ingredient" means an extract comprising at least one molecule, preferably a set of molecules having a cosmetic effect, particularly when applied topically, in particular the cosmetic effect being a complexion-perfecting effect.

[0028] For the purposes of this invention, "complexion perfector" means a visible and measurable improvement in the overall appearance of facial skin, manifested in particular by a uniformity of skin color, an increase in the brightness and natural radiance of the skin, or an improvement in the reflection and diffusion of light by the skin.

[0029] Characterization of the active principle

[0030] The present invention therefore relates to the cosmetic use of an active principle obtained from the species Myrtus communis for a complexion-perfecting effect.

[0031] This active ingredient is a hydrolysate of Myrtus communis, said hydrolysate comprises at least 20% carbohydrates and less than 10% polyphenols in total dry matter of the hydrolysate.

[0032] Total sugars were determined using the DUBOIS method (Dubois M. et al., Analytical chemistry, 28, 3, 350-356, 1956). Preferably, the active ingredient comprises between 20% and 50% carbohydrates in the total dry matter of the hydrolysate.

[0033] The carbohydrate composition and their molar masses were determined respectively by ion chromatography and by HPLC with DEDL detection (evaporative light scattering detector). Preferably, the carbohydrates present in the hydrolysate are predominantly composed of glucose, fructose, and galacturonic acid. Most preferably, at least 70% of the carbohydrates in the hydrolysate are glucose, fructose, and galacturonic acid. The molar mass of the carbohydrates is between 180 and 16,000 Da. Most preferably, at least 70% of the carbohydrates in the hydrolysate have a molar mass less than 720 Da.

[0034] The uronic acid content is determined by reaction with sodium tetraborate giving a pink color in the presence of metahydroxydiphenyl allowing for measurement by spectrophotometer.

[0035] The quantification of polyphenols was carried out by colorimetric assay compared to a gallic acid standard curve. The polyphenol content of the active ingredient according to the invention is at most 10% by weight of the total dry matter of the hydrolysate, preferably between 3 and 8% by weight of the total dry matter of the hydrolysate. An analysis of the polyphenols constituting the hydrolysate was carried out by liquid chromatography coupled with mass spectrometry and UV detection. The identification of the principal species was carried out by comparing the exact masses of the ions detected by MS and the fragments obtained by MS / MS to the standards for these molecules.

[0036] The polyphenols of the hydrolysate are preferably polyphenols from the group consisting of ellagitannins, gallotannins, phenolic acids, hydroxybenzoic acids, and their mixture.

[0037] The inventor also determined the ash and protein content of the active ingredient according to the invention.

[0038] The protein content is determined by the Kjeldhal method (reference: Official method of analysis of the AOC 1975, 12th ed. W. Horwitz, ED, New York, pp. 15-60). The molar mass of the proteins present in the hydrolysate according to the invention was determined by FPLC (Fast Protein Liquid Chromatography). This shows that the majority of peptides in the hydrolysate according to the invention advantageously have a molar mass of less than 2,000 Da.

[0039] Finally, the crude ash content is determined by weighing the residues from incineration at 550°C in an electric muffle furnace and represents at most 40% by weight of dry matter, preferably between 30 and 40% by weight of dry matter of the hydrolysate.

[0040] According to a particularly preferred object, the hydrolysate is obtained by a process comprising the following steps: - solubilization of Myrtus communis leaf powder in water in an acidic medium, - enzymatic hydrolysis, - separation of soluble and insoluble phases by filtration, centrifugation or decantation, - thermal treatment, - purification of the soluble fraction by absorption onto an adjuvant, - concentration of the active fraction, - filtration, and sterilizing filtration.

[0041] Also, a first form of the active principle according to the invention is obtained comprising at least the hydrolysate of Myrtus communis as described above.

[0042] The cosmetic active ingredient according to the invention may also advantageously include at least one other ingredient such as a preservative, an antioxidant, a stabilizer, an atomizing support, a mineral filler, a polymer, a plasticizer, a surfactant and / or a combination thereof.

[0043] The hydrolysate present in the cosmetic active ingredient can then be in liquid form or in solid form or in film form.

[0044] When presented in liquid form, the active ingredient may consist of Myrtus communis hydrolysate accompanied by a stabilizer and / or preservation system.

[0045] The hydrolysate in liquid form is preferably in the form of a clear liquid solution, with a characteristic odor and an amber color.

[0046] When in liquid form, the dry matter content of the hydrolysate can be determined by weighing the residues obtained from drying the hydrolysate according to the invention at 105°C in an oven until a constant weight is obtained. Preferably, the hydrolysate according to the invention in liquid form has a dry matter content of between 20 and 200 g / L, preferably between 28 and 42 g / L.

[0047] In the case where it is in solid form, the active ingredient could consist of the hydrolysate of Myrtus communis as previously described and a carrier chosen from maltodextrin, gum arabic or soy lecithin. According to In a particularly suitable embodiment, the hydrolysate represents at least 10% by weight of the active ingredient and the carrier at most 90% by weight of the active ingredient.

[0048] In the case of a solid form in which the active ingredient is associated with a carrier, the levels of polyphenols, sugars and proteins relative to dry matter in the active ingredient can be modified since the carriers (maltodextrin, gum arabic) are exclusively saccharides.

[0049] The active ingredient can also be presented in the form of a film as described in patent FR3079145. In this case, the hydrolysate of Myrtus communis represents at least 0.1% by weight of the film.

[0050] When in film form, the active ingredient comprises: - at least the hydrolysate of Myrtus communis according to the invention. - at least one mineral charge, and - at least one polymer of natural origin, and - at least one plasticizer, and - at least one surfactant.

[0051] The polymer of natural origin can be chosen from: pectin, tamarind gum, alginate, pullulan, psyllium, xanthan gum, guar gum, tara gum, carob gum, agar, gum arabic, gellan gum, dextran, carrageenan, cellulose, konjac and chitosan.

[0052] The plasticizer can be chosen from: glycerol, sorbitol, sucrose, erythritol, urea, propylene glycol and butylene glycol.

[0053] The mineral filler can be chosen from: calcium carbonate, green clay, kaolin, perlite, talc, magnesium silicate, mica, diatomaceous sericite, silica, calcium sulfate, calcium chloride, potassium chloride, iron oxide and zinc oxide.

[0054] Finally, the active ingredient may also include a pigment for coloring the film.

[0055] Cosmetic composition

[0056] The active ingredient as described above is intended to be incorporated into a composition, in particular a composition comprising at least 0.1% by weight of said active ingredient and a physiologically acceptable medium, preferably a cosmetically acceptable medium.

[0057] These compositions may be in the form of oil-in-water emulsions, water-in-oil emulsions, multiple emulsions (Water / Oil / Water or Oil / Water / Oil), which may be microemulsions or nanoemulsions, or in the form of solutions, suspensions, hydrodispersions, aqueous gels, powders, foundation, or films. They may be more or less fluid and have the appearance of creams, emulsions, gels, masks, or any other appearance known to those skilled in the art.

[0058] Preferably, it may consist of compositions comprising between 0.1 and 20% of the active ingredient, in particular in liquid form, more preferably between 0.5 and 10%.

[0059] These compositions comprise, in addition to the active ingredient, a physiologically acceptable medium such as a cosmetically acceptable medium, that is to say, one which does not cause any discomfort to the user such as redness, tightness or tingling.

[0060] The compositions according to the invention may also contain as an ingredient at least one compound selected from: - oils, which can be chosen in particular from among silicone oils, linear or cyclic, volatile or non-volatile, - waxes, such as ozokerite, polyethylene wax, beeswax or camauba wax, - silicone elastomers, - surfactants, preferably emulsifying, whether non-ionic, anionic, cationic or amphoteric, - co-surfactants, such as linear fatty alcohols, - thickeners and / or gelling agents, - humectants, such as polyols like glycerin, - colorings, preservatives, fillers, - the tensors, - the sequestrators, - perfumes, - and their mixtures, without this list being exhaustive.

[0061] Examples of such ingredients are cited in particular in the International Cosmetic Ingredient Dictionary and Handbook published by the Personal Care Product Council.

[0062] Of course, a person skilled in the art will take care to choose any additional compounds, active or inactive, and their quantity, in such a way that the advantageous properties of the mixture are not, or substantially not, altered by the envisaged addition.

[0063] Process for preparing Myrtus communis hydrolysate

[0064] The hydrolysate constituting or contained in the active ingredient according to the invention can be obtained by any means.

[0065] However, according to a preferred embodiment, the extraction process includes at least one extraction step from Myrtus communis, namely at least one hydrolysis, preferably at least one enzymatic hydrolysis.

[0066] According to a particularly suitable embodiment, the active ingredient as described above is obtained by carrying out the following steps: - Solubilization of Myrtus communis leaf powder in water, preferably in an acidic medium, - Extraction by hydrolysis, preferably enzymatic hydrolysis - Separation of soluble and insoluble phases, - thermal treatment, - purification of the soluble fraction, preferably by absorption onto an adjuvant, - concentration of the active fraction, - filtration, and sterilizing filtration.

[0067] The heat treatment step is advantageously carried out to inactivate the enzyme(s) present. This inactivation is then carried out according to the recommendations of the supplier of the enzyme(s) used.

[0068] Purification is advantageously carried out by absorption on an adjuvant.

[0069] The hydrolysate obtained at this stage may optionally be further concentrated. Preferably the hydrolysate is purified, preferably by successive filtration steps through membranes of different porosity, retaining the molecules of interest at each step and / or by a chromatographic method.

[0070] The extract obtained after hydrolysis and purification is a hydrolysate of Myrtus communis, and constitutes a first form of the active principle according to the invention, then being in liquid form.

[0071] Another form of the active ingredient according to the invention is obtained after hydrolysis, purification and concentration and is also in liquid form.

[0072] The resulting hydrolysate can then be dried and, with or without a support, to obtain a solid form. This phase can be carried out by performing the following steps: - an atomization support, preferably maltodextrin, is added to the Myrtus communis hydrolysate, at most 90% (by mass / volume); - this solution is then concentrated under vacuum; - an antimicrobial treatment can be carried out; - Atomization allows us to obtain a powder.

[0073] The steps of the processes described above, taken individually, are usual in the field of extractions of active ingredients from natural raw materials and a person skilled in the art is able to adjust the reaction parameters on the basis of their general knowledge.

[0074] Cosmetic use according to the invention

[0075] Thus, the invention aims at the cosmetic use of a cosmetic active ingredient according to any of the embodiments previously described, for its complexion-perfecting effect, on healthy skin.

[0076] This active ingredient preferentially improves the radiance of the complexion, in particular by increasing the transmission of light through the stratum comeum, more preferably by decreasing the amount of oxidized proteins

[0077] Mitochondrial activity is also increased, in particular mitochondrial integrity, and / or mitochondrial dynamics, and / or mitophagy, and / or ATP production. The active ingredient thus acts beneficially on mitochondrial activity as a whole, resulting in increased radiance of the complexion. Indeed, mitochondria are considered to be essential for a radiant complexion.

[0078] More preferably, the active ingredient increases the expression of aconitase, and / or THSP27, and / or SIRT6, and / or SIRT3.

[0079] The invention is now illustrated by non-limiting examples of compositions according to the invention and by results. Examples

[0080] Example 1

[0081] The active ingredient of Example 1 is obtained from myrtle of the species Myrtus communis. The active ingredient of Example 1 is obtained by the following process: - Solubilization of Myrtus communis powder in water in an acidic medium, preferably Myrtus communis leaf powder, - enzymatic hydrolysis, - separation of soluble and insoluble phases by filtration, centrifugation or decantation, - inactivation by heat treatment. - purification of the soluble fraction by absorption onto an adjuvant, - concentration of the active fraction, - filtration, and - sterilizing filtration.

[0082] The active ingredient according to Example 1 consists of an extract of Myrtus communis possessing in particular the following characteristics: - Dry matter content = 33.7 g / L, of which: - Protein content = 0.98%, by weight relative to total dry matter, - Ash content = 30.3% by weight relative to total dry matter, - Total sugar content = 36.8% by weight relative to dry matter total, - Polyphenol content = 5.3% by weight relative to total dry matter.

[0083] Evaluation of the effect of the active ingredient as a complexion perfector

[0084] Since it is not possible to select human keratinocytes with a "dull complexion" and it is known that aged skin has a duller, lackluster complexion, the following studies are conducted on normal and aged human keratinocytes.

[0085] Test 1 - In vitro evaluation of the effect of the active ingredient on the synthesis of SIRT3 and SIRT6.

[0086] The objective of this study is to evaluate the effect of the active ingredient on the synthesis of sirtuins 3 and 6. The syntheses of SIRT3 and SIRT6 were evaluated by immunohistofluorescence on reconstructed epidermis, obtained from normal human keratinocytes and aged by successive replications.

[0087] The protocol is as follows. On day 0 (D0), human keratinocytes are seeded and then incubated at 37°C. From day 4 (D4) to day 11 (D11), the culture medium is changed every 2 days. On day 14 (D14), the epidermis is exposed to the active ingredient at concentrations of 0.05% and 0.10% (v / v) or without. On day 16 (D16), the reconstructed epidermis is retrieved, fixed, dehydrated, and embedded in paraffin. Sections are prepared using a microtome. SIRT3 and SIRT6 synthesis is then analyzed by immunohistofluorescence according to the knowledge of those skilled in the art.

[0088] The results are presented in Table 1 below.

[0089] [Tables 1] SIRT3 Synthesis (xO3 UA) Capacity to restore SIRT3 synthesis (%) SIRT6 Synthesis (UA) Capacity to restore SIRT6 synthesis (%) Reconstructed normal epidermis Control 293 1191 ACTIVE INGREDIENT 0.10% 455 1205 Reconstructed aged epidermis Control 92 852 ACTIVE INGREDIENT 0.05% 208 + 58 1025 + 51 ACTIVE INGREDIENT 0.10% 299 + 103 1093 + 71

[0090] The synthesis of SIRT3 and SIRT6, described as regulating mitochondrial function, is significantly reduced with aging. Tested at 0.10%, the active ingredient significantly restores the synthesis of SIRT3 and SIRT6 by 103% and 71%, respectively, thus restoring the action of these sirtuins on mitochondria, as will be detailed later.

[0091] Test 2 - In vitro evaluation of the effect of the active ingredient on the control of mitochondrial integrity.

[0092] The objective of this study is to evaluate the effect of the active ingredient on the control of mitochondrial integrity.

[0093] Two markers are particularly involved in mitochondrial quality control: - HSP27 (Heat Shock Protein 27), a chaperone protein involved in cell survival; - aconitase, the true bodyguard of the mitochondria, which acts both on metabolism and on the preservation of mitochondrial DNA.

[0094] The expression of HSP27 was studied in young and aged human keratinocytes by quantitative PCR. The protocol is as follows. On day 0 (D0), human keratinocytes are seeded and incubated at 37°C. On day 3 (D3), the keratinocytes are treated with medium in the presence or absence of the active ingredient at 0.05% (V / V). On day 5 (D5), the RNAs were reverse-transcribed and the resulting complementary DNAs were analyzed by quantitative PCR. The quantification of fluorescence incorporation is continuously measured using a thermocycler.

[0095] Aconitase synthesis was evaluated by immunohistofluorescence on reconstructed epidermis, produced from normal human keratinocytes and aged by successive replications according to the same protocol as that described in trial 1.

[0096] The results are presented in Tables 2 and 3 below.

[0097] [Tables2] HSP27 expression (%) Increase in HSP27 expression / control (%) Young donor keratinocytes Control 100 ACTIVE INGREDIENT 0.05% 152 + 52 Older donor keratinocytes Control 79 ACTIVE INGREDIENT 0.05% 126 + 59

[0098] [Tables3] Aconitase synthesis (xO₄ UA) Capacity to restore aconitase synthesis (%) Normal reconstructed epidermis Control 218 ACTIVE INGREDIENT 0.10% 328 Aged reconstructed epidermis Control 98 ACTIVE INGREDIENT 0.05% 182 + 70 ACTIVE INGREDIENT 0.10% 218 + 100

[0099] HSP27 expression and aconitase synthesis are significantly decreased during aging. Tested at 0.05% on aged keratinocytes, the active ingredient significantly increases HSP27 expression by 59% and significantly restores aconitase synthesis by 70%.

[0100] Thus, the active ingredient acts favorably on the synthesis of two key players in the control of mitochondrial integrity.

[0101] Test 3 - In vitro evaluation of the effect of the active ingredient on mitochondrial dynamics.

[0102] The objective of this study is to evaluate the effect of the active ingredient on mitochondrial dynamics.

[0103] In cases of moderate cellular damage, the dynamic properties of mitochondria are called upon. Indeed, these organelles possess a capacity for continuous remodeling that ensures the homogeneity of a functional mitochondrial population. This remodeling is characterized by two states: - fusion, a compensatory phenomenon that allows a damaged mitochondrion to mix with a healthy mitochondrion to maintain the homogeneity of the mitochondrial population; - fission, a sequestration phenomenon, corresponding to the fragmentation of a damaged mitochondrion to generate two mitochondria: a first healthy one and a second damaged one, which will be eliminated by mitophagy.

[0104] This study was carried out by labeling with fluorescent probes on human keratinocytes from young and old donors. The protocol is as follows.

[0105] Young and aged human keratinocytes are seeded and incubated at 37°C. On day 2, the keratinocytes are treated with medium in the presence or absence of the active ingredient at 0.05% and 0.10% (v / v) and then incubated at 37°C. On day 3, the cells are labeled with fluorescent probes. Visualization is performed using a confocal microscope coupled with an image analysis system.

[0106] The mitochondrial network aspect ratio parameter is quantified for each cell. The aspect ratio corresponds to the ratio of the mitochondrial length to the mitochondrial width. The more fragmented the mitochondrial network, the lower the aspect ratio will be.

[0107] The results are presented in Table 4 below.

[0108] [Tables4] Aspect ratio (%) Ability to restore the aspect ratio (%) Young donor keratinocytes Control 2,792 Old donor keratinocytes Control 2,402 ACTIVE INGREDIENT 0.05% 2,793 + 100 ACTIVE INGREDIENT 0.10% 2,803 + 103

[0109] With aging, the morphology of the mitochondrial network is altered. The aspect ratio is significantly decreased in human keratinocytes from aged donors compared to keratinocytes from young donors. Tested at 0.10%, the active ingredient significantly restores the aspect ratio to 103%.

[0110] Thus, the active ingredient restores the morphology of the mitochondrial network. [YES] Trial 4 - In vitro evaluation of the effect of the active ingredient on mitophagy.

[0112] The objective of this study is to evaluate the effect of the active ingredient on mitophagy. In cases of significant cellular damage that could compromise cell survival, mitochondria are selectively eliminated by mitophagy. This biological process is a form of autophagy that allows for the specific recruitment of damaged mitochondria by autophagosomes. This process leads to the formation of mitophagosomes and the elimination of defective mitochondria. Mitophagosome formation was analyzed by studying the colocalization between the markers GRP75 (mitochondria) and LC3 (autophagosomes), direct evidence of mitochondrial removal by mitophagy. This study was performed using immunocytofluorescence on normal human keratinocytes subjected to CCCP (carbonyl cyanide m-chlorophenylhydrazone) stress, a potent mitochondrial membrane depolarizing agent known to induce mitophagy.

[0113] The protocol is as follows. Human keratinocytes are seeded and incubated at 37°C, then the keratinocytes are treated with medium containing or not containing CCCP, in the presence or absence of the active ingredient. Immunostaining is performed on day 3. Visualization is performed using a confocal microscope coupled to an image analysis system.

[0114] The results are presented in Table 5 below.

[0115] [Tableaux5] Number of mitophagosomes (%) Increase in mitophagosomes (%) Control 5.77 Stressed control 10.74 Active ingredient 0.025% 11.21 + 4 Active ingredient 0.050% 14.93 + 39

[0116] CCCP treatment of keratinocytes leads to activation of mitophagy. Tested at 0.05% on keratinocytes subjected to free radical stress, the active ingredient significantly increased the percentage of mitophagosomes by 39%. Thus, the active ingredient improves mitochondrial activity by eliminating defective mitochondria.

[0117] Test 5 - In vitro evaluation of the effect of the active ingredient on ATP production.

[0118] The objective of this study is to evaluate the effect of the active ingredient on production Adenosine triphosphate (ATP). ATP is produced in the mitochondria. It is the main source of energy for most cellular functions. At the skin level, ATP is essential for various processes such as epidermal differentiation and renewal.

[0119] Intracellular ATP levels were measured by bioluminescence on normal human keratinocytes from young and old donors using a suitable kit.

[0120] The results are presented in Table 6 below.

[0121] [Tableauxô] ATP Production (pM) Capacity to Preserve ATP Production (%) Young Donor Keratinocytes Control 2.41 ACTIVE INGREDIENT 0.10% 3.04 Aged Donor Keratinocytes Control 1.61 ACTIVE INGREDIENT 0.025% 1.91 +38 ACTIVE INGREDIENT 0.05% 1.95 +43 ACTIVE INGREDIENT 0.10% 2.01 +50

[0122] Thus, the active ingredient reactivates the production of energy necessary for proper cellular functioning.

[0123] Test 6 - In vivo evaluation of the complexion-perfecting effect of the active ingredient.

[0124] The objective of this study is to evaluate in vivo the complexion-perfecting action of the active ingredient formulated at 2% in emulsion, compared to a placebo formula in Caucasian and Asian volunteers.

[0125] The Caucasian panel consisted of two groups of approximately twenty healthy female volunteers, aged 51 to 69 years, who applied either the placebo or the 2% active ingredient to the entire face twice daily for 14 days. The complexion-perfecting effect was evaluated on the Caucasian panel by studying the level of oxidized proteins and assessing skin radiance (clinical scoring by experts).

[0126] The Asian panel consisted of 34 healthy female volunteers, aged 55 to 76 years, who applied the placebo and the 2% active ingredient to half of their face twice daily for 56 days. The complexion-perfecting effect was evaluated on the Asian panel by a dermatologist through skin radiation analysis.

[0127] Protein carbonylation (addition of a carbonyl group, C=O) is an irreversible modification of the structure which contributes to the reduction of light transmission of the stratum corneum, thus modifying the quality of the appearance of the skin.

[0128] The results of the study of the rate of oxidized proteins on a Caucasian panel are presented in Table 7 below.

[0129] [Tables7] Day 0 Day 14 Change Day 14 / Day 0 Control 31.5 30.6 -2.8 ACTIVE INGREDIENT 2% 33.4 24.8 -25.8 Change / Control (%) -23.0

[0130] From 14 days of twice-daily application and compared to the group that used the placebo formula, the active ingredient formulated at 2% in emulsion significantly reduces the amount of oxidized proteins present on the skin surface of Caucasian subjects by 23.0%.

[0131] This effect was observed in 95% of volunteers who applied the active ingredient compared to 58% of volunteers in the placebo group. By reducing the formation of oxidized proteins, the active ingredient thus improves the transmission of light through the stratum corneum, resulting in improved skin radiance.

[0132] The results of the complexion radiance study on a Caucasian panel are presented in Table 8 below.

[0133] [Tables8] Day 0 Day 14 Variation Day 14 / Day 0 (%) Radiation Control 5.7 5.6 -1.7 ACTIVE INGREDIENT 2% 5.5 6.0 8.9 Change / Control (%) 10.6 Pink color Control 1.9 1.9 0.0 ACTIVE INGREDIENT 2% 1.7 2.1 21.4 Change / Control (%) 21.4 Olive color Control 3.8 3.8 0.3 ACTIVE INGREDIENT 2% 4.1 3.6 -12.7 Change / Control (%) -13.0 Eye fatigue Control 5.6 5.5 -1.3 ACTIVE INGREDIENT 2% 5.8 5.0 -14.0 Change / Control (%) -12.8

[0134] Compared to the group using the placebo formula, the active ingredient formulated at 2% in emulsion significantly improves the characteristic parameters of the radiance of the complexion of Caucasian volunteers.

[0135] Indeed, after 14 days of treatment, the active ingredient makes the complexion brighter and fresher by significantly increasing skin radiance by 10.6% and pinkness by 21.4%. These effects are observed in 67% of the volunteers who applied the active ingredient, compared to 37% and 32% respectively of the subjects who applied the placebo.

[0136] The active ingredient also improves the appearance of a healthy complexion by reducing olive eye color by 13.0% and eye fatigue by 12.8%. This effect was observed in 67% and 76% of volunteers who applied the active ingredient, respectively, compared to only 37% and 58% with the use of the placebo.

[0137] These results are supported by the appreciation of the volunteers themselves, who all rated their skin as brighter after 14 days of treatment.

[0138] The results of the study of cutaneous radiation by a dermatologist on an Asian panel are presented in Table 9 below.

[0139] [Tables9] Variation J28 / J0 Variation J56 / J0 Control 1.2 5.6 Active ingredient 2% 7.1 15.5 Variation / control 6.0 10.1

[0140] The results of the study of the homogeneity of the complexion by a dermatologist on an Asian panel are presented in Table 10 below.

[0141] [Tables 10] Change Day 28 / Day 0 Change Day 56 / Day 0 Control 12.9 14.7 Active ingredient 2% 17.2 23.3 Change / control 4.3 8.6

[0142] After 28 days of twice-daily application by Asian volunteers and compared to the placebo area, the active ingredient formulated at 2% in emulsion significantly improves the radiance of the complexion by increasing the skin radiance assessed by a dermatologist by +6.0% and the homogeneity of the complexion (assessed by the volunteers themselves) by +4.3%.

[0143] This effect intensifies after 56 days of twice-daily application, with an increase in skin radiance of +10.1% and in skin tone evenness of +8.6%. By limiting protein oxidation and improving skin radiance, the active ingredient, formulated at 2% in emulsion, enhances the complexion of Caucasian and Asian volunteers.

[0144] Example 2: Cosmetic composition

[0145] An example of a formulation comprising the active ingredient in the form of a lotion is shown in Table 11 below.

[0146] [Tableauxll] Ingredients % Al Purified Water qsp 100 Sodium Benzoate 0.300 Pentylene Glycol 5.000 A2 Anhydrous Citric Acid 0.070 Aqua (Water) & Tetrasodium Glutamate Deionate 0.600 A3 Butylene Glycol 3.000 Acacia Senegal Gum & Xanthan Gum 1.000 Sclerotium Gum 0.200 A4 Sargassum Fluitans / Natans Extract & Se ed Oil & Ascorbyl Palmitate & Tocopherol 0.015 C Active Principle 2.000 D Citric Acid Solution 10% qs pH

[0147] The composition of example 2 can in particular be obtained by the following process: - Under gentle stirring, add A2 to Al. - Under shearing agitation, add A3, then A4. Shake until homogeneous. - Emulsify B in A under shear agitation for 20 minutes. - Under moderate agitation, add C. - Adjust the pH to 4.8 - 5.2 with D

[0148] The composition then takes the form of a soft, shiny, off-white lotion.

[0149] Example 3: Cosmetic composition

[0150] An example of a formulation comprising the active ingredient in the form of a cream is shown in Table 12 below.

[0151] [Tables 12] Ingredients % Al Purified Water qs 100 Sodium Gluconatel 0.30 Sodium Benzoate 0.30 Pentylene Glycol 5.00 Butylene Glycol 3.00 A2 Glycerin 2.00 Sclerotium Gum & Xanthan Gum 0.30 B Sucrose Polystearate & Cetyl Palmitate 3.00 Sodium Stearoyl Glutamate 0.50 Glyceryl Stearate 1.50 Theobroma Cacao (Cocoa) Seed Butter 3.00 Caprylic / Capric Triglyceride 9.00 Propanediol Dicaprylate 7.00 Lecithin & Helianthus Annuus (Sunflower) Seed Oil & Ascorbyl Palmitate & Tocopherol & Rosmarinus Officinalis (Rosemary) Extract 0.05 C Principle Active 2.00 D Citric Acid Solution 10% qs pH

[0152] The composition of example 2 can in particular be obtained by the following process: - Add A2 to Al while stirring and heat to 80°C. - Place B under agitation and heat to 80°C. - Emulsify B in A under shear agitation for 10 minutes. - At room temperature, with gentle stirring, add C. - Adjust the pH to 4.8-5.2 with D.

[0153] The composition then appears as a thick, glossy emulsion, off-white in color.

[0154] Example 4: Cosmetic composition

[0155] An example of a formulation comprising the active ingredient according to the invention in the form of a night cream is shown in Table 13 below.

[0156] [Tables 13] Ingredients % Al Purified Water qsp 100 Sodium Benzoate 0.300 Disodium EDTA 0.300 Pentylene Glycol 5.000 Butylene Glycol 3.000 A2 Glycerin 2.000 Xanthan Gum 0.200 B PEG-100 Stearate & Glyceryl Stearate 3.000 Cetearyl Alcohol & Cetearyl Glucoside 2.000 Pentaerythrityl Distearate 1.200 C10-18 Triglycerides 3.000 Isocetyl Stearate 5,000 Dimethicone 2,500 Jojoba Esters & Jojoba Alcohol & Propanediol & Tocopherol 4,000 Diisopropyl Sebacate 7,000 BHT 0.005 Lecithin & Helianthus Annuus (Sunflower) Seed Oil & Ascorbyl Palmitate & Tocopherol & Rosmarinus Officinalis (Rosemary) Extract 0.010 C Polyacrylate-13 & Polyisobutene & Polysorbate 20 1.000 D Active Principle 2.000 E Citric Acid Solution 10% qs pH

[0157]

[0158] The composition of example 4 can notably be obtained by the following process: - Add A2 to Al while stirring and heat to 80°C. - Place B under agitation and heat to 80°C. - Emulsify B in A under shear agitation for 10 minutes. - At room temperature, with gentle stirring, add C then D. - Adjust the pH to 4.8 - 5.2 with E. The composition then appears as a thick, glossy emulsion, off-white in color.

Claims

Demands

1. Cosmetic use of an active ingredient comprising a hydrolysate of Myrtus communis comprising at least 20% carbohydrates and less than 10% polyphenols in total dry matter of the hydrolysate, for a complexion-perfecting effect.

2. Use according to the preceding claim intended to improve the radiance of the complexion by increasing the transmission of light through the stratum corneum, preferably by decreasing the amount of oxidized proteins.

3. Use according to any one of the preceding claims intended to increase mitochondrial activity.

4. Use according to the preceding claim, intended to increase mitochondrial integrity, mitochondrial dynamics, mitophagy and ATP production.

5. Use according to any one of the preceding claims, intended to increase the expression of aconitase, HSP27, SIRT6 and SIRT3.

6. Use according to any one of the preceding claims, wherein the hydrolysate is an enzymatic hydrolysate.

7. Use according to any one of the preceding claims, wherein the carbohydrates of the hydrolysate are composed mainly of fructose, glucose and galacturonic acid.

8. Use according to any one of the preceding claims, wherein the polyphenols of the hydrolysate are ellagitannins, gallotannins, phenolic acids or hydroxybenzoic acids.

9. Use according to any one of the preceding claims, wherein the hydrolysate is obtained by a process comprising the following steps: - solubilization of Myrtus communis leaf powder in water in an acidic medium, - enzymatic hydrolysis, - separation of the soluble and insoluble phases by filtration, centrifugation or decantation, - heat treatment, - purification of the soluble fraction by absorption onto an adjuvant, concentration of the active fraction, filtration, and sterilizing filtration.