New cosmetic uses of an extract from the microalga Tetradesmus obliquus

Abstract

The present invention relates in particular to the cosmetic or nutraceutical use of an extract of the microalga Tetradesmus obliquus or of an oily ingredient comprising it to increase the pigmentation of the skin and / or hair, advantageously of the hair, and / or to maintain the homogeneity of the complexion and / or to prepare the skin for tanning and / or to promote relaxation and well-being.

Description

Title of the invention: New cosmetic uses of an extract of the microalga Tetradesmus obliquus. Field of the invention

[0001] The present invention relates to the cosmetic or nutraceutical use of an extract of Tetradesmus obliquus or an oily ingredient containing it to increase the pigmentation of the skin and / or hair, advantageously of the hair, and / or to maintain an even complexion and / or to prepare the skin for tanning and / or to promote relaxation and well-being. Said Tetradesmus obliquus extract or the oily ingredient containing it also has a sun protection boosting effect. Prior art

[0002] Melanogenesis is a natural biological process corresponding to an increase in melanin synthesis by specialized cells called melanocytes. These cells are located in the basal lamina of the epidermis, above the dermis. The melanin thus produced is then transferred to the upper layers of the skin, particularly to keratinocytes, via melanosomes, structures specific to melanocytes. Responsible for the pigmentation of the skin and its appendages, the melanin produced by melanocytes thus plays a role in the evenness of skin tone and prepares the skin for tanning.

[0003] It is indeed known that UV rays, particularly UV-A, directly affect the dermis by inducing the production of reactive oxygen species (ROS) and increasing the activity of metalloproteinases, which are responsible, among other things, for the degradation of the dermal fibers. The well-known consequence is premature skin aging and the appearance of unsightly pigment spots.

[0004] The paradox is that the sun has a positive effect on health, at least by acting positively on individuals' well-being. It is known that sun exposure helps reduce stress by lowering cortisol levels, so that people spontaneously seek the benefits of sun exposure. Known as the stress hormone, cortisol is secreted by the adrenal glands following stimulation of the pituitary gland via adrenocorticotropic hormone (ACTH) and plays an important role in the immune system, metabolism, and sleep. However, it is also known that cortisol is produced by keratinocytes and melanocytes in the epidermis. In fact, these cells possess all the enzymatic machinery to synthesize cortisol de novo from cholesterol. Furthermore, they respond to ACTH stimulation.

[0005] However, aware of the harmful effects on their skin, people who expose themselves to the sun wish to protect themselves from UV rays and / or to prepare their skin for sun exposure.

[0006] In this context, oral use of supplements containing L-tyrosine, carrot extract, grape seed extract, steviol, or carotenoids such as lycopene is already known to increase skin pigmentation or prolong the effects of tanning. However, very few topical cosmetic solutions exist. Therefore, there is a need in the cosmetics industry for the availability of effective and natural alternative ingredients. In the nutraceutical field, there is also a need for alternative solutions. Furthermore, the sunscreens present in sunscreens to protect the skin from UV radiation are known for their physical barrier effect on the skin against UV rays. However, these filters are difficult to formulate, are not natural, and are not always free from impact on human health or on ecosystems, particularly marine ecosystems.Therefore, in the cosmetics sector in particular, there is a need for natural ingredients that are not harmful to health and that do not have a negative impact on the environment.

[0007] Unexpectedly, the Applicant discovered that an extract of the microalga Tetradesmus obliquus was particularly effective at pigmenting the skin and its appendages while maintaining an even skin tone, thus preparing the skin for tanning. Furthermore, as will be demonstrated later in the application, this extract has shown its effectiveness in promoting relaxation and well-being after topical application. By increasing skin and appendage pigmentation on the one hand, and promoting relaxation and well-being on the other, without any UV exposure, the extract exhibits effects mimicking the beneficial effects of UV rays (skin pigmentation, relaxation, and well-being).

[0008] Furthermore, the Applicant has shown that this extract, in combination with organic or inorganic UV filters, enhances the sun protection provided by said UV filters. The extract is said to be a sun protection booster. By protecting the skin from UV rays, the extract has the advantage of being a complete natural ingredient that can be used both as a tanning preparation and as UV protection. Thus, the extract according to the invention will be advantageously used in compositions for the prevention and / or treatment of the harmful effects of UV radiation on the skin and / or its appendages.

[0009] The extract according to the invention is a natural, non-irritating solution for the skin, obtained from a microalgae biomass cultivated under controlled conditions. It is easily incorporated into a cosmetic or nutraceutical formulation and is produced quickly and easily on an industrial scale.

[0010] The microalga Tetradesmus obliquus belongs to the Scenedesmaceae family, which includes more than a dozen distinct species. The species T. obliquus has 2 distinct morphotypes.

[0011] Application CN110236994 describes an anti-aging cosmetic composition comprising an extract of Phaeodactylum tricomutum, an extract of Euglena minuta, and an extract of Scenedesmus obliquus, the latter being described for its antioxidant activity. Application EP3381442 describes a cosmetic composition comprising an aqueous or dry extract of a modified strain of Scenedesmus rubescens as an anti-aging cosmetic composition protecting the skin from the effects of electromagnetic radiation. This is a distinct strain, and the cosmetic applications are different.

[0012] Thus, to the Applicant's knowledge, nothing describes the use of an extract of Tetradesmus obliquus to increase the pigmentation of the skin and / or hair, to maintain the homogeneity of the complexion and / or to prepare the skin for tanning, and / or to promote relaxation and well-being, nor the use of such an extract as a sun protection booster agent. Description of the invention

[0013] A first object relates to the cosmetic use of an extract of the microalga Tetradesmus obliquus or of an oily ingredient comprising it to increase the pigmentation of the skin and / or of the hair, advantageously of the hair, and / or to maintain the homogeneity of the skin tone and / or to prepare the skin for tanning and / or to promote relaxation and well-being.

[0014] A second object relates to a cosmetic composition for topical application to the skin and / or its appendages comprising, in a physiologically acceptable medium:

[0015] (i) an oily ingredient comprising: - From 0.5% to 5% by weight, or even more advantageously between 0.5% and 3.5% by weight of Tetradesmus obliquus extract relative to the total weight of the oily ingredient, - From 0.05% to 1% by weight of vitamin E relative to the total weight of the oily ingredient, advantageously from 0.06% to 0.25% by weight, and - From 96% to 99.45% by weight of a vegetable oil, preferably a medium-chain triglyceride (MCT) oil and preferably coconut oil, relative to the total weight of the oily ingredient and

[0016] (ii) optionally also at least one cosmetically acceptable excipient chosen in particular from additional oils such as vegetable oils chosen in particular from argan oil, shea oil, jojoba oil, avocado oil, sweet almond oil, or any oil extracted from a plant or algae, including a microalga, in particular selected from olive oil, rapeseed oil, linseed oil, sunflower oil, a medium chain triglyceride (MCT) oil, C11-C13 alkanes, ester oils and mixtures thereof, preservatives, emulsifiers, emollients, surfactants, moisturizers, thickeners, shine enhancers, texturizing agents, film-forming agents, organic or mineral sunscreens, pigments, colorants, perfumes, biological additives, chelating agents, astringents, polymers, reducing agents, pH regulators, humectants, conditioning agents, and mixtures thereof.

[0017] Another object relates to the nutraceutical use of Tetradesmus obliquas extract or an oily ingredient comprising it to increase the pigmentation of the skin and / or hair, advantageously of the hair, and / or to maintain the homogeneity of the skin tone and / or to prepare the skin for tanning and / or to promote relaxation and well-being.

[0018] Another object relates to a cosmetic or nutraceutical skincare process for the skin and / or its appendages to increase the pigmentation of the skin and / or appendages, advantageously of the hair, and / or to maintain the homogeneity of the complexion and / or to prepare the skin for tanning, and / or to promote relaxation and well-being, comprising (i) the topical application to the skin and / or its appendages of an extract of Tetradesmus obliquus or of an oily ingredient comprising it as defined according to the invention, or of a cosmetic composition comprising it as defined in the invention, or (ii) the oral administration of an extract of Tetradesmus obliquus or of an oily ingredient comprising it as defined in the invention or of a nutraceutical composition comprising it as defined in the invention.

[0019] The present invention further relates to the cosmetic or nutraceutical, non-therapeutic use of an extract of Tetradesmus obliquus or an oily ingredient comprising it, as defined in the invention, in combination with at least one UV filter present in the same composition or in a separate composition, as an agent to enhance the sun protection effect provided by the UV filter(s). Another object relates to an oily ingredient comprising an extract of Tetradesmus obliquus as defined in the invention, or a topical cosmetic composition as defined in the invention, or a nutraceutical composition as defined in the invention, for use in the prevention and / or treatment of the adverse effects of UV radiation on the skin and / or its appendages.

[0020] The term “cosmetic use” or “nutraceutical use” means a non-therapeutic use, which is neither pharmaceutical nor dermatological according to A specialist in the field, a dermatologist. The product is not intended for use in treating skin or skin appendages requiring therapeutic treatment, but rather for skin or skin appendages considered healthy. "Healthy skin" here refers to skin free from injury, lesion, scar, allergy, wound, redness, infection, and / or dermatological disorders such as vitiligo, acne, and / or dermatitis. For the purposes of this invention, skin includes the scalp. Similarly, for the purposes of this invention, skin exposed to the sun is considered healthy skin that does not require therapeutic treatment.

[0021] For the purposes of this invention, "topical application" means the direct application or spraying of the extract or the oily ingredient comprising it onto at least one area of ​​skin on the face and / or body, the body area being chosen from any area of ​​the arms, shoulders, legs, thighs, back, torso, chest, neck, feet and / or hands, and / or buttocks. "Facial area" means any area chosen from the cheeks, cheekbones, forehead, contour of the nose, nasolabial folds, temples, contour of the eyes, chin, and / or contour of the mouth. "Phanera" means hair.Advantageously, the extract according to the invention or the oily ingredient comprising it is applied topically to at least one area of ​​the body and / or face and / or hair, the body area being chosen from the décolleté, face, arms, shoulders, stomach, legs and the hair being advantageously the hair.

[0022] Thus the uses described within the framework of the present invention are intended for healthy skin and / or healthy hair and nails. Detailed description of the invention

[0023] A first object therefore relates to the cosmetic use of an extract of the microalga Tetradesmus obliquas or of an oily ingredient comprising it to increase the pigmentation of the skin and / or of the hair, advantageously of the hair, and / or to maintain the homogeneity of the skin tone and / or to prepare the skin for tanning, and / or to promote relaxation and well-being.

[0024] By "increasing skin and / or hair pigmentation" it is understood that the extract according to the invention is capable of increasing melanin synthesis from melanocytes, resulting in skin browning or hair pigmentation, observable with the naked eye. Advantageously, the extract according to the invention is capable of increasing by at least 5%, advantageously by at least 10% or even by at least 16%, the amount of melanin measured in vitro in a melanocyte culture in the presence of the Tetradesmus obliquus extract according to the invention, advantageously the crude extract of T. obliquus as described in Example 1a), under the conditions detailed in Example 2a) (Table 1).

[0025] In another embodiment of the invention, "increasing skin pigmentation and / or hair growth" means increasing by an average of 15%, in particular by an average of 20%, or even 30%, the skin color measured on skin expiants in the presence of the oily ingredient comprising the crude extract of T. obliquas according to the invention compared with the skin color measured on the control expiants without extract (coconut oil) under the conditions detailed in Example 2b) (Table 2).

[0026] In yet another embodiment of the invention, "increasing the pigmentation of the skin and / or hair" means increasing by at least 1.7%, advantageously by more than 2%, the pigmentation index measured in vivo by colorimetry in the presence of the oily ingredient comprising the crude extract of T. obliquus according to the invention, compared to an oily ingredient without extract, in the context of an in vivo study conducted under the conditions described in Example 2c) (Tables 3 and 4).

[0027] Alternatively, “increasing skin and / or hair pigmentation” means decreasing the luminance parameter (L*) measured by chromametry in the same in vivo study detailed in Example 2c). In an advantageous embodiment of the invention, the decrease in luminance L* is more than 1.5% compared to the beginning of the study, advantageously more than 2.5%. The results are presented in Table 5.

[0028] In yet another embodiment, the extract of T. obliquus and advantageously the oily ingredient comprising it is effective in increasing hair pigmentation. Advantageously, the increase in hair pigmentation is measured in an in vivo study within a population of individuals with white hair, advantageously a proportion of white hair of at least 5%, preferably at least 10%, and most preferably at least 15%.

[0029] Furthermore, the extract of T. obliquus, and particularly the oily ingredient comprising it, has a skin tone homogeneity maintenance effect, advantageously concomitant with its pigmenting effect. Here, "skin tone homogeneity maintenance" means a non-significant difference over the measurement time of the luminance parameter L* measured between different parts of the abdomen of the study population in vivo, under the conditions detailed in Example 2c) (Table 6), and advantageously before skin exposure to UV radiation.

[0030] The extract of T. obliquus, and particularly the oily ingredient comprising it, is also effective in maintaining skin pigmentation under UV light. "Maintaining skin pigmentation under UV light" means maintaining the skin's pigmentation index when UV stress is applied to the skin. It is known that exposure to Sunlight causes skin pigmentation. In an advantageous embodiment, the pigmentation index is measured chromametrically via the luminance parameter L* after exposure to UV-A rays, within the framework of the in vivo study as described in Example 2c). The results are presented in Table 7.

[0031] Thus, by naturally increasing skin pigmentation, that is, without UV exposure, the T. obliquas extract, the oily ingredient containing it, and the cosmetic composition containing the oily ingredient are specifically designed to prepare the skin for tanning. Therefore, for the purposes of this invention, "preparing the skin for tanning" means increasing skin pigmentation before UV exposure.

[0032] Based on the principle that melanin synthesized by melanocytes migrates to the upper layers of the epidermis via melanosomes, that keratinocytes and melanocytes are capable of synthesizing cortisol, the so-called stress hormone, and that sun exposure is known to decrease levels of this hormone, it was found, in a particularly surprising way, that the extract of T. obliquas, and more specifically the oily ingredient containing it, had the effect of decreasing cortisol levels, and thus promoting relaxation and well-being. In particular, by "promoting relaxation and well-being," we mean decreasing cortisol levels after topical application to the skin of the population in the in vivo study described above, of the cream containing the oily ingredient according to the invention, compared to the cortisol levels measured after application of the placebo cream, in the context of the in vivo study described in Example 2c).

[0033] In an advantageous embodiment of the invention, this involves a decrease in cortisol levels of at least 25% greater in the presence of the oily ingredient, compared to the cortisol level measured in the group that received the placebo cream. Advantageously, the cortisol level is measured after saliva samples are collected, under the conditions described in Example 4. The results are presented in Table 8. Cortisol is synthesized locally by keratinocytes and melanocytes. A decrease in the overall cortisol level measured in saliva can therefore be correlated with a decrease in the cortisol level in the epidermis after topical application of the oily ingredient according to the invention, the cortisol synthesized locally by the keratinocytes then being transported.

[0034] The extract and more advantageously the oily ingredient which comprises it therefore have the ability to mimic the beneficial effects of the sun, without exposure to it: both by increasing the pigmentation of the skin and / or hair, but also by promoting relaxation and well-being.

[0035] The Applicant also showed in Example 5 that the extract, and more advantageously the oily ingredient comprising it, has the capacity, in the presence of UV filters (organic and inorganic bases illustrated in example 5), to increase the sun protection provided by said UV filters and thus increase the protection of the sun filter against UV.

[0036] The term "to increase the protection of the sunscreen against UV rays" refers to the ability of the T. obliquas extract, and more advantageously the oily ingredient containing it, to increase the effectiveness of sunscreens against UV rays. For the purposes of this invention, "UV rays" refers to both UV-A and UV-B rays, and "sunscreen" or "UV filter" refers to both mineral filters, organic filters, and mixtures thereof, preferably mineral filters. Mineral sunscreens, unlike organic filters, do not penetrate the epidermis; their action consists of reflecting UV rays. Zinc oxide and titanium dioxide are examples. Organic filters, on the other hand, penetrate the skin and protect it by inactivating UV rays through a chemical reaction. Octinoxate, oxybenzone, and avobenzone are examples of organic filters and their active ingredients.The extract according to the invention, and advantageously the oily ingredient comprising it, are herein referred to as sunscreen activators or "SPF boosters" or "sunscreen boosters." In an advantageous embodiment of the invention, the oily ingredient comprising the T. obliquus extract increases UV protection by raising the SPF and / or UVA index of mineral and / or organic sunscreens, compared to the SPF or UVA index calculated in the control (mineral or organic base only) under the conditions detailed in Example 5. The results are shown in Table 9. By increasing skin and / or hair pigmentation, and by increasing sunscreen protection against UV radiation, the T. obliquus extract according to the invention, and more advantageously the oily ingredient comprising it, are useful for increasing skin protection against UV radiation.

[0037] Finally, the Applicant has also shown that the T. obliquus extract, and in particular the oily ingredient comprising it, has a protective effect against the harmful effects of UV radiation. In particular, Example 6 demonstrates the ability of the extract according to the invention to reduce inflammation induced by UV rays. Specifically, this reduction in inflammation is reflected in the maintenance of the interleukin IL-8 level measured in the in vivo study already described (Example 2c and Example 6) after skin exposure to UV-A rays. The results are presented in Table 10. Obtaining extracts

[0038] According to a particular embodiment of the invention, the culture of Tetradesmus obliquus is conducted under controlled conditions within dedicated systems such as open culture tanks of the "race-ways" or "open bonds" type, or closed systems of the photobioreactor type. The photobioreactors may be photobioreactors Horizontal or vertical tubular photobioreactors, planar or columnar. Advantageously, within the scope of the invention, microalgae culture is carried out in photobioreactors, advantageously horizontal tubular photobioreactors. Microalgae culture is performed according to batch, fed-batch, continuous, semi-continuous, turbidostat, or chemostat culture modes.

[0039] For the purposes of this invention, "Tetradesmus obliquas extract" means any extract—referred to interchangeably as crude or dry extract—obtained from any biomass produced from any culture of the microalga Tetradesmus obliquus. This crude extract is therefore distinct from the oily ingredient as defined later in this description.

[0040] The biomass obtained from the culture can be used fresh or frozen and / or dried before extract preparation. It can be concentrated by removing all or part of the water using processes selected from centrifugation, filtration, flocculation, sedimentation, coupled or not to drying steps by freeze-drying, vacuum drying, drum drying, spray drying, or any other process that reduces the water content of the biomass. Cell lysis processes can then be implemented, such as the application of pressure, electric currents, shear forces, the use of enzymes, or any other process that disrupts the structure of tissues, organs, cells, or organelles.

[0041] Herein, "dry biomass" means dehydrated microalgal biomass comprising less than 15%, advantageously less than 10%, and even more advantageously less than 5% water. Preferably, in the context of the invention, the biomass obtained after cultivation is frozen before drying. The biomass may be pre-centrifuged and then filtered to remove residual water before extraction.

[0042] According to a particular embodiment of the invention, the extract is obtained by extraction in a solvent or a mixture of solvents selected from water, acetone, butanone, hexane, ethyl acetate, methyltetrahydrofuran, 2-methyloxolane, heptane, an alcohol selected from ethanol, methanol, isopropanol, a natural or branched oil, a glycol, a polyol, an alcohol / water mixture, or glycol / water in a proportion of 99 / 1 to 1 / 99 (w / v), or by supercritical CO2 extraction.

[0043] In one embodiment of the invention, the biomass extraction is a solid-liquid extraction in the presence of a solvent or solvent mixture selected from water, acetone, butanone, hexane, ethyl acetate, methyltetrahydrofuran, 2-methyloxolane, heptane, an alcohol selected from ethanol, methanol, isopropanol, a natural or branched oil, a glycol, a polyol, an alcohol / water mixture, or glycol / water in a proportion of 99 / 1 to 1 / 99 (w / v).

[0044] The solid-liquid extraction of biomass according to the invention is generally carried out from a quantity of biomass of 0.1 to 20% by weight, advantageously from 1% to 20% by weight, very advantageously from 5% to 15% by weight, and even more advantageously 11% by weight relative to the total volume of biomass and extraction solvent.

[0045] The extraction can be carried out at a temperature ranging from 4°C to 300°C, preferably from 15°C to 120°C, and even more preferably from 4°C to 80°C, including ambient temperature, i.e. a temperature of 25°C. It is advantageously carried out at a temperature between 20°C and 50°C, and even more advantageously at 30°C.

[0046] According to a first embodiment of the invention, biomass extraction is carried out in water under subcritical conditions, at a temperature ranging from 100°C to 300°C, advantageously from 120°C to 250°C, and further advantageously at 120°C. Extraction can be carried out at a given temperature or at successively increasing temperatures. In an advantageous embodiment of the invention, extraction is carried out at a temperature of 120°C. In an alternative embodiment, it will be conducted along a gradient of three increasing temperatures between 100°C and 200°C, such as 120°C, 140°C then 160°C or 110°C, 130°C then 150°C, or even 120°C, 145°C then 170°C.Extraction under "subcritical conditions" refers to extraction in the presence of water, at temperatures above 100°C and pressures below 221 bar. The water remains in a liquid state but has a viscosity and surface tension lower than that of water at ambient temperature, thus increasing its dielectric constant. The extraction pressure is therefore between 150 and 250 bar, preferably between 200 and 221 bar, advantageously in a pressure extraction autoclave.

[0047] According to another embodiment of the invention, biomass extraction is carried out by supercritical CO2 extraction. In this case, said extraction may optionally be conducted in the presence of a co-solvent selected from ethanol, acetone, methanol, or any combination thereof. Alternatively, supercritical CO2 extraction may be carried out alone without the presence of a co-solvent and followed by a further extraction with a polar solvent selected from ethanol, acetone, methanol, hexane, heptane, advantageously ethanol. Advantageously, within the scope of the invention, supercritical CO2 extraction is carried out in the presence of ethanol (10%) as a co-solvent. The supercritical CO2 extraction conditions are such that the pressure measured in bar is greater than 74 bar, advantageously greater than 100 bar, and further advantageously greater than 150 bar.According to this embodiment, the temperature is above 35°C, advantageously above 45°C, and even more advantageously above 50°C.

[0048] According to a particular and preferred embodiment of the invention, the extract of Tetradesmus obliquas is obtained by solid-liquid extraction in an alcohol / water, in a proportion of 99 / 1 to 1 / 99 (w / v), advantageously even in a proportion of 95 / 5 to 90 / 10 (w / v). Advantageously, the extract is obtained by extraction in ethanol as the sole solvent.

[0049] Thus, in a first advantageous embodiment of the invention, the extract is obtained from frozen and then dried Tetradesmus obliquas biomass by solid-liquid extraction in ethanol as the sole solvent at a temperature of 30°C. The quantity of biomass used for the extraction is advantageously 5% to 15% by weight, and even more advantageously 11% by weight, relative to the total volume of the biomass and solvent. The crude extract obtained is decolorized with activated carbon and then filtered under the conditions described in Example 1a).The residual ethanol is evaporated and then the extract can be used as is ("crude extract") in powder form or dispersed in an oil (in which case it will be referred to as "oily extract" or "oily ingredient" according to the invention) or incorporated into a final cosmetic composition (incorporation of the crude extract or the oily ingredient into the final cosmetic composition), comprising at least one cosmetically acceptable excipient as defined in the rest of the description.

[0050] According to a second advantageous embodiment, the Tetradesmus obliquus extract is obtained from frozen and then CO2-dried biomass by supercritical CO2 extraction at a temperature of 50°C and a pressure of 150 bar in the presence of ethanol as a co-solvent (10%). The extract obtained is rinsed with water and then filtered under the conditions described in Example 1b).

[0051] In a particular embodiment of the invention, the Tetradesmus obliquus extract comprises a lutein content of less than 3% by weight relative to the total weight of the composition. Advantageously, the extract comprises a total carotenoid content, particularly in 3-carotene, α-carotene, and zeaxanthin, other than lutein, of less than or equal to 3% by weight relative to the total weight of the extract. Further advantageously, said extract does not comprise lycopene. Obtaining the oily ingredient#:

[0052] In one embodiment of the invention, the Tetradesmus obliquus extract (crude extract) is dispersed in at least one vegetable oil, thus forming an oily ingredient, also referred to as an oily preparation of Tetradesmus obliquus. This oily ingredient can be incorporated into a final cosmetic or nutraceutical composition, comprising a cosmetic or nutraceutical excipient, or can be used alone, as such.

[0053] In an advantageous embodiment, the Tetradesmus obliquus extract is dispersed in any oil extracted from a plant or alga, including a microalga, and in particular selected from olive oil, rapeseed oil, linseed oil, oil Sunflower oil is a medium-chain triglyceride (MCT) oil. Medium-chain triglycerides (MCTs) are defined as esters of glycerol and saturated fatty acids, whose hydrocarbon chain has 6 to 12 carbon atoms. A medium-chain triglyceride oil can be chosen from coconut oil, advantageously coconut oil, palm oil, and palm oil, but can also be obtained from other fats or oils. Advantageously, in the context of the invention, the vegetable oil is a medium-chain triglyceride oil, most advantageously coconut oil.

[0054] According to a particular method, said oil is present in an amount by weight ranging from 50 to 99.8% by weight relative to the total weight of the composition, advantageously from 75% to 99.5% by weight relative to the total weight of the oily ingredient, and further advantageously from 96% to 99.45%. The oily ingredient can be used as is or as an intermediate preparation in a nutraceutical composition or a cosmetic composition further comprising other ingredients and excipients such as those described above.

[0055] In a preferred embodiment of the invention, the oily ingredient comprises coconut oil. According to a particular and preferred embodiment for topical cosmetic use, the Tetradesmus obliquas extract obtained according to examples 1a) or 1b), is supplemented with an amount of coconut oil ranging from 96% to 99.45% by weight relative to the total weight of the oily ingredient. Thus, the content of Tetradesmus obliquas extract (crude extract) ranges from 0.5% to 5% by weight, and advantageously from 0.5% to 3.5% by weight relative to the total weight of the oily ingredient.

[0056] Advantageously, the oily ingredient comprises a vitamin E content ranging from 0.05% to 1% by weight relative to the total weight of the oily ingredient, and advantageously a content ranging from 0.06% to 0.25% by weight, most advantageously 0.1%. For the purposes of this invention, "vitamin E" means a tocopherol selected from α-tocopherol, γ-tocopherol, β-tocopherol, or β-tocopherol, or a tocotrienol selected from α-tocotrienol, β-tocotrienol, γ-tocotrienol, or β-tocotrienol. Advantageously, it is α-tocopherol.

[0057] Thus, according to a particular and preferred method, the extract of Tetradesmus obliquus is included in an oily ingredient comprising: - From 0.5% to 5% by weight, or even more advantageously between 0.5% and 3.5% by weight of Tetradesmus obliquus extract relative to the total weight of the oily ingredient, - From 0.05% to 1% by weight of vitamin E relative to the total weight of the oily ingredient, advantageously from 0.06% to 0.25% by weight, and - From 96% to 99.45% by weight of a vegetable oil, preferably a medium chain triglyceride (MCT) oil and preferably coconut oil, relative to the total weight of the oily ingredient.

[0058] In a particular embodiment of the invention, the oily ingredient comprises a lutein content of less than 0.05% by weight relative to the total weight of the oily ingredient, preferably less than 0.02% (w / w). Advantageously, the oily ingredient comprises a total carotenoid content, particularly of 3-carotene, α-carotene, and zeaxanthin, other than lutein, of less than or equal to 0.05% by weight, preferably less than 0.02% by weight relative to the total weight of the oily ingredient. Most advantageously, the oily ingredient does not comprise lycopene. Cosmetic composition

[0059] Another object of the invention relates to a cosmetic composition for topical application to the skin and / or its appendages comprising, in a physiologically acceptable medium:

[0060] (i) an oily ingredient comprising: - From 0.5% to 5% by weight, or even more advantageously between 0.5% and 3.5% by weight of Tetradesmus obliquas extract relative to the total weight of the oily ingredient, - From 0.05% to 1% by weight of vitamin E relative to the total weight of the oily ingredient, advantageously from 0.06% to 0.25% by weight, and - From 96% to 99.45% by weight of a vegetable oil, preferably a medium-chain triglyceride (MCT) oil and preferably coconut oil, relative to the total weight of the oily ingredient and

[0061] (ii) optionally, in addition, at least one cosmetically acceptable excipient selected in particular from additional oils such as vegetable oils, in particular argan oil, shea oil, jojoba oil, avocado oil, sweet almond oil, or any oil extracted from a plant or algae, including microalgae, in particular olive oil, rapeseed oil, linseed oil, sunflower oil, a medium-chain triglyceride (MCT) oil, C11-C13 alkanes, ester oils and mixtures thereof, preservatives, emulsifiers, emollients, surfactants, moisturizers, thickeners, shine enhancers, texturizing agents, film-forming agents, organic or mineral sunscreens, pigments, colorants, perfumes, biological additives, chelating agents, agents astringents, polymers, reducing agents, pH regulating agents, humectants,Conditioning agents, and mixtures thereof.

[0062] According to a particular embodiment of the invention, the cosmetic composition of the invention as defined above further comprises at least one UV filter selected from an organic UV filter, an inorganic UV filter, and mixtures thereof.

[0063] The cosmetic composition therefore generally comprises at least one cosmetically acceptable excipient and the Tetradesmus obliquas extract, more advantageously the oily ingredient comprising it. Advantageously, the oily ingredient is included in the cosmetic composition at a weight content relative to the total weight of the composition ranging from 0.1% to 10% by weight, advantageously from 0.25% to 5% by weight, and further advantageously from 1.5% by weight relative to the total weight of the composition.

[0064] The cosmetic composition advantageously takes the form of a cream, lotion, gel, soap, spray, oil, oil-in-water or water-in-oil emulsion, aerosol, foam, ointment, serum, stick, powder, sunless tanning product, dry shampoo, shampoo, hair coloring solution, conditioner, skin or hair mask, leave-in hair treatment, or hairspray. It may also be encapsulated in the form of spheres, microspheres, or liposomes. Advantageously, it takes the form of a cream, spray, or oil.

[0065] The cosmetic composition is useful for increasing the pigmentation of the skin and / or hair, advantageously of the hair. It also helps to promote relaxation and well-being.

[0066] The cosmetic composition may also include any cosmetic ingredient or active ingredient having a similar or identical effect of increasing the pigmentation of the skin and / or hair, with or without a synergistic effect. As such, any pro-pigmenting active ingredient and / or plant active ingredient may be used in combination and advantageously those chosen from among tyrosine, vitamin D, dihydroxyacetone, sage extract, rosemary extract, Buriti oil (Mauritia flexuosd), carrot oil, Chaulmoogra oil, annatto extract (Bixa orellana Y) and mixtures thereof.

[0067] The cosmetic composition may also include any active ingredient having an effect complementary to that of the invention, and in particular any active ingredient for skin and / or hair hydration, and / or any anti-aging active ingredient, whether it acts on skin firmness or as an anti-wrinkle active. In this respect, the Tetradesmus obliquus extract, and more advantageously the oily ingredient containing it, may be combined with one or more microalgae extracts, and in particular an extract of the microalga Phaeodactylum tricomutum, known as an anti-aging active, advantageously an ethanolic extract, or further advantageously, the commercially available extract. an oily ingredient marketed by the Applicant under the name PhycoAge™ as a plumping active ingredient; or an ethanolic extraction co-product of P. tricomutum marketed by the Applicant under the name PhycoSi™ to exfoliate the skin, reduce its microrelief, and increase cell renewal. Also mentioned is an extract of the microalga Tisochrysis lutea and, advantageously, an ethanolic extract marketed by the Applicant under the name Luteana™, providing a soothing effect on the skin and maintaining homeostasis.Finally, the cosmetic composition may include an extract of Porphyridium cruentum, in particular that marketed by the Applicant under the name Renouvellance™ for its protective effect against UV rays and pollution, and / or an extract of the microalga Dunaliella tertiolecta, in particular that marketed by the Applicant under the name DunaPure™ for its skin-purifying effect, its soothing effect and its effect on reducing imperfections.

[0068] In a particularly advantageous embodiment of the invention, the cosmetic composition comprises a lutein content of less than 0.002% by weight relative to the total weight of the cosmetic composition, preferably less than 5 x 10⁴%. Advantageously, the cosmetic composition comprises a total carotenoid content, particularly of 3-carotene, α-carotene, and zeaxanthin, other than lutein, of less than or equal to 0.001%, preferably less than 5 x 10⁴% relative to the total weight of the cosmetic composition. Most advantageously, the cosmetic composition does not comprise lycopene.

[0069] The cosmetic composition is useful for increasing the pigmentation of the skin and / or hair, advantageously of the hair, and / or for maintaining an even complexion. It also prepares the skin for tanning.

[0070] Another object of the invention relates to the nutraceutical use of an extract of Tetradesmus obliquas or an oily ingredient containing it to increase the pigmentation of the skin and / or its appendages, advantageously of the hair, and / or to maintain an even complexion and / or to prepare the skin for tanning, and / or to promote relaxation and well-being. The nutraceutical use is advantageously carried out orally. Advantageously, the T. obliquus extract is as defined in this application.The extract is thus advantageously obtained by extraction in a solvent or mixture of solvents selected from water, acetone, butanone, hexane, ethyl acetate, methyltetrahydrofuran, 2-methyloxolane, heptane, an alcohol selected from ethanol, methanol, isopropanol, a natural or branched oil, a glycol, a polyol, an alcohol / water mixture, or glycol / water in a proportion of 99 / 1 to 1 / 99 (w / v), or alternatively by supercritical CO2 extraction. Preferably, the extract of T. obliquas is obtained by extraction in ethanol as the sole solvent.

[0071] The extract of T. obliquus is used in proportions suitable for oral nutraceutical use. It is advantageously contained within an oily ingredient. Thus, for oral nutraceutical use, the oily ingredient comprises: - A content ranging from 8% to 79.85% by weight, advantageously from 20% to 50% by weight, in weight relative to the total weight of the oily ingredient, of Tetradesmus obliquus extract. - From 0.15% to 1.25% by weight relative to the total weight of the oily ingredient, advantageously from 0.5% to 1% by weight of vitamin E. - From 20% to 90% by weight and advantageously from 60% to 90% by weight of coconut oil, relative to the total weight of the oily ingredient.

[0072] By increasing the pigmentation of the skin and / or hair, advantageously of the hair, the extract of T. obliquus according to the invention and more advantageously the oily ingredient comprising it, is useful orally to maintain the homogeneity of the complexion and / or to prepare the skin for tanning, and / or to promote relaxation and well-being.

[0073] The extract of T. obliquus, and advantageously the oily ingredient comprising it, is incorporated into a nutraceutical composition. Herein, "nutraceutical composition" means interchangeably a food supplement, a nutritional supplement, a nutraceutical supplement, or a nutraceutical supplement.

[0074] Preferably in this case, the content of oily ingredient by weight in relation to the total weight of the nutraceutical composition ranges from 10% to 70% by weight, advantageously it ranges from 20% to 50% by weight.

[0075] Advantageously, the nutraceutical composition comprises at least one orally acceptable excipient. "Orally acceptable" here means an inert excipient that is non-toxic to humans. The orally acceptable excipient is selected from among supporting agents, bulking agents, preservatives, acidifying agents, emulsifying agents, humectants, gelling agents, lubricating agents, coating or encapsulating agents, stabilizing or dispersing agents, sweetening agents, and mixtures thereof. It can be ingested orally safely and without side effects. Among the supporting agents, we will mention maltodextrin, acacia gum, cellulose and its derivatives (methylcellulose, ethylcellulose and microcrystalline cellulose), calcium phosphate, inulins, flours (rice flour, coconut or other), starches and their derivatives, talc, or even carob gum.Preservatives are chosen from sodium sorbate or sodium benzoate; acidifying agents are chosen from. Specifically, citric acid or sodium citrate may be used as emulsifiers; lecithin, phospholipids, and polyethylene glycols may be used as emulsifiers; glycerin, sorbitol, and dextrose may be used as humectants. Bulking agents may include mannitol, lactose, sorbitol, starch, microcellulose, hydroxypropyl methylcellulose, crosscarmelose, polyvinylpyrrolidone, calcium phosphate (anhydrous or hydrated di- and tribasic), citric acid or tartaric acid, sodium, potassium, or calcium carbonates, silica cellulose, or acacia gum. Among the lubricating agents (anti-caking agents), we will mention magnesium stearate, stearic acid, lecithins, colloidal silica, a rice extract, talc, glycerol dibehenate, or a bamboo extract standardized in silica.Coating or encapsulating agents can be chosen from gelatin, hydroxypropyl methylcellulose, pululan, beeswax, or camauba wax. Gelling agents can be chosen from native or pregelatinized starches, carrageenan, pectin, alginates, agar-agar, xanthan gum, or gelatin. Stabilizing or dispersing agents include alginates, acacia gum, and phospholipids. Finally, sweetening agents include maltitol, xylitol, sucralose, sorbitol, agave syrup, glucose syrup, sucrose, fructose, stevia extract, honey, isomalt, or maltitol. The excipient is advantageously present in the composition according to the invention in quantity, by weight relative to the total weight of the composition, ranging from 1% to 90% by weight, advantageously between 1% and 50% by weight, further advantageously between 1.5% and 10% by weight relative to the total weight of the composition.

[0076] Advantageously, the nutraceutical composition is presented in a form suitable for oral administration, selected from a capsule, softgel, tablet, lozenge, orodispersible tablet, orodispersible granule, pill, orodispersible lozenge, softgel, syrup, ampoule, or suspension. In a particular embodiment, the nutraceutical composition is not presented in the form of a lozenge or chewing gum.

[0077] This nutraceutical composition is effective in increasing skin and / or hair pigmentation, advantageously hair pigmentation, and / or in maintaining even skin tone and / or in preparing the skin for tanning, and / or in promoting relaxation and well-being.

[0078] In a particular embodiment of the invention, the nutraceutical composition comprises a lutein content of less than 0.15% by weight relative to the total weight of the composition. Advantageously, the nutraceutical composition comprises a total carotenoid content, particularly of 3-carotene, α-carotene, and zeaxanthin, other than lutein, of less than or equal to 0.2% by weight. Further advantageously, the nutraceutical composition does not comprise lycopene. Cosmetic or nutraceutical treatment process

[0079] Another object of the invention relates to a cosmetic or nutraceutical skincare method for the skin and / or its appendages to increase the pigmentation of the skin and / or appendages, advantageously of the hair, and / or to maintain the homogeneity of the complexion and / or to prepare the skin for tanning, and / or to promote relaxation and well-being, comprising (i) the topical application to the skin and / or its appendages of an extract of Tetradesmus obliquas or of an oily ingredient comprising it as defined above, or of a cosmetic composition comprising it as defined above, or (ii) the oral administration of an extract of Tetradesmus obliquus or of an oily ingredient comprising it as defined above or of a nutraceutical composition comprising it as defined above.

[0080] The cosmetic care process is thus particularly dedicated to preparing the skin for tanning.

[0081] In an advantageous embodiment of the invention, the cosmetic treatment process comprises applying the Tetradesmus obliquus extract, the oily ingredient comprising it, or the cosmetic composition comprising said extract or said oily ingredient, to at least one area of ​​the body and / or face and / or hair, the body area being advantageously chosen from the décolleté, face, arms, shoulders, abdomen, and legs, and the hair being advantageously chosen from the hair. Other uses

[0082] Another object of the invention relates to the cosmetic or nutraceutical, non-therapeutic use of a Tetradesmus obliquus extract or an oily ingredient containing it, as defined above, in combination with at least one UV filter present in the same composition or in a separate composition, as an agent to enhance the sun protection effect provided by the UV filter(s). The Tetradesmus obliquus extract or an oily ingredient containing it will also be referred to as an "SPF booster" or "sun protection booster" effect when combined with at least one UV filter, the UV filter(s) being in the same composition as the extract according to the invention or in a separate composition.

[0083] According to a first mode, the oily extract or ingredient according to the invention and the UV filter(s) are in the same cosmetic composition for topical application on the skin and / or its appendages.

[0084] According to another embodiment, the extract or oily ingredient according to the invention is in a topical cosmetic composition A and the UV filter(s) are in a topical cosmetic composition B separate from composition A, compositions A and B being able to be applied to the skin and / or its appendages simultaneously or sequentially, Preferably, composition A with the extract or oily ingredient is applied before composition B.

[0085] According to yet another embodiment, the extract or oily ingredient according to the invention is in an oral nutraceutical composition A and the UV filter(s) are in a topical cosmetic composition B, compositions A and B being able to be used simultaneously or sequentially, preferably composition A with the extract or oily ingredient is administered before (tanning preparation effect) and / or during (sun protection booster effect) the application of composition B.

[0086] Another object of the invention relates to an oily ingredient comprising an extract of Tetradesmus obliquas as defined above, or a topical cosmetic composition as defined above, or a nutraceutical composition as defined above, for use in the prevention and / or treatment of the adverse effects of UV radiation on the skin and / or its appendages.

[0087] The present invention also relates to the use of a composition comprising the extract or oily ingredient according to the invention for the manufacture of a composition for use in the prevention and / or treatment, in a subject, of the adverse effects of UV radiation on the skin and / or its appendages. The present invention also relates to the use of a composition comprising the extract or oily ingredient according to the invention for the prevention and / or treatment, in a subject, of the adverse effects of UV radiation on the skin and / or its appendages. The present invention also relates to a method for preventing or treating the adverse effects of UV radiation on the skin and / or its appendages in a subject in need, comprising the topical or oral administration to the subject of an effective amount of a composition comprising the extract or oily ingredient according to the invention.

[0088] Examples referring to the description are given below for illustrative purposes only and shall not limit the scope of the invention. Unless otherwise stated, temperature is expressed in degrees Celsius (°C), pressure in bar, and percentages are given on a weight-by-weight basis (w / w). Ppm means parts per million (0.01% = 100 ppm). Examples

[0089] Example 1: Methods of obtaining extracts of Tetradesmus obliquas

[0090] The Tetradesmus obliquus strain used in the context of the invention was first isolated in Germany in 1976. Two distinct strains were used in the context of the invention and were obtained from the collections of the University of Austin, Texas, USA (Culture Collection of Algae, strain UTEX 393) and the Culture Collection of Algae & Protozoa (CCAP 276 / 48). These are Tetradesmus obliquus strains.

[0091] The microalga T. obliquus was cultured under autotrophic conditions in a 5000 L photobioreactor, under controlled temperature, pH, and light conditions (pH maintained at 8.0; controlled temperature of 24°C; constant light of 50 pmol.m².s⁻¹). The culture was harvested at the end of the exponential growth phase, and the biomass was then separated from the culture medium by centrifugation. The culture medium was discarded.

[0092] Example 1a) Once separated from its culture medium by centrifugation, the T. obliquus biomass was frozen and then dried. An amount of Tetradesmus obliquus biomass representing 11% by weight relative to the total volume of biomass and solvent was then extracted in ethanol as the sole solvent at a temperature of 30°C. The extract thus obtained (referred to interchangeably as 'extract' or 'crude extract') was decolorized with activated carbon and then filtered. The residual ethanol was evaporated. The crude extract is in liquid form. It can be used as is or dried by freeze-drying to obtain a powder.

[0093] Example 1b) Once separated from its culture medium by centrifugation, the T. obliquus biomass was frozen and then dried. The T. obliquus biomass was then extracted by supercritical CO2 extraction at a temperature of 50°C and a pressure of 150 bar in the presence of ethanol as a co-solvent (10%). The resulting extract was rinsed with water and then filtered. The extract obtained (referred to interchangeably as 'extract' or 'crude extract') is in liquid form. It can be used as is or freeze-dried to obtain a powder. Ex.lc) Obtaining oily ingredients

[0094] The crude liquid extracts obtained in examples 1a) and 1b) can be used as such or each dispersed in coconut oil to obtain the oily ingredient of the invention as follows.

[0095] For topical cosmetic use, a final concentration of 2% by weight of Tetradesmus obliquus crude extract relative to the total weight of the oily ingredient was dispersed in 97.5% coconut oil, and then a final concentration of 0.5% α-tocopherol was added. For nutraceutical use (oral route), a final concentration of 20% by weight of Tetradesmus obliquus crude extract relative to the total weight of the oily ingredient was dispersed in 79.5% coconut oil, and then a final concentration of 0.5% α-tocopherol was added.

[0096] These oily ingredients can be used alone in liquid form (oil) or dried to obtain a powder. They can be incorporated into cosmetic or nutraceutical compositions.

[0097] Example 2: Increased skin pigmentation in the presence of a extract of Tetradesmus obliquus

[0098] Example 2a) Measurement of the increase in melanin levels

[0099] Protocol: Adult human melanocytes (NHEM) were suspended and seeded in two sets of 24-well plates and then cultured in commercially available MGM-4 (Mélanocyte Growth Medium-4) for 72 hours. The first plate was used to measure melanin levels. The second plate was used to measure cell density. The plates were subjected to the following protocol: 72 hours post-seedling, the culture medium was discarded and replaced with a culture medium containing the crude extract of T. obliquas (as shown in example 1a) at a final volume concentration of 0.05% or 0.1% relative to the total volume of the culture medium and extract. The same culture medium without the extract (MGM-4 as a replacement) (Negative Control) was cultured under identical conditions.The media were cultured for 3 days at 37°C (Air / CO2 95% / 5%) and then rinsed with phosphatin saline buffer (PBS). The media in the plate used to measure melanin levels were extracted in the presence of NaOH-DMSO extraction buffer. The extracts were heated (80°C) for 2 hours and then aliquoted into a 96-well plate. Absorbance was read at 405 nm (SPARK® microplate reader, Tecan™). A standard curve (Synthetic Melanin, Sigma) was established to calculate the melanin level in each well. The mean was calculated for each experimental medium (n=4). The media in the plate used to measure cell density were treated with neutral red and then extracted with a solution of acetic acid and ethanol. Absorbance was read at 540nm (standard range established with a titrated suspension of synthetic melanin).The mean cell density was calculated for each experimental medium (n=4). The melanin level was then related to the cell density and is expressed in picograms / cell (pg / cell). The percentage increase in melanin level is compared to the negative control (Table 1).

[0100] Results: Table 1

[0101] [Tables 1] Mean melanin content (pg / cell) Standard deviation Mean melanin content (%) Negative control 46.30 2.47 100 Crude extract of T. obliquus Example 1a) 0.05% final (v / v) 54.00* 2.61 117 Crude extract of T. obliquus Example 1a) 0.1% final (v / v) 61.76* 3.70 134

[0102] (*p<0.01, Student's t-test)

[0103] Conclusion: Tetradesmus obliquus extract significantly increased melanin levels at the tested concentrations, up to 17% at a dose of 0.05% (v / v) and up to 34% at a dose of 0.1% (v / v). The extract is therefore particularly effective as a pro-pigmenting agent and exhibits a dose-response effect of interest.

[0104] Example 2b) Measurement of the increase in melanin levels on skin expiants

[0105] Protocol: Skin expiants from the abdomen of a healthy 30-year-old Caucasian donor, stored at a temperature of 37°C (5% CO2), were distributed into 4 different experimental groups.

[0106] The expiants were cultured for a period of 24 hours in the presence of renewed culture medium, then the oily ingredient according to example (a) diluted in coconut oil (at a rate of 1.5% w / w) (30 qL / cm2) or the same oily ingredient comprising only coconut oil (100%) as a control, was applied topically for a total period of 3 days on the expiants (30 qL / cm2). A positive control consisting of vitamin D3 diluted in coconut oil (Vit-D3, Cholecalciferol, Sigma-Aldrich C9756; 0.1 qg in 30 qL / cm²) was also applied. The topical application was repeated 24 hours after the first application. A negative control without the application of any oily ingredient was conducted. After a 24-hour period following the second topical application, the expiry samples were collected.After a 3-hour culture period, the expiry samples were collected and then frozen at -80°C for in situ analysis of the increase in melanin levels as follows.

[0107] Sections of explants (5 µm thick) were obtained and fixed with an ethanolic solution (95%) containing 5% acetic acid. Fontana-Masson staining was performed (Sigma-

[0108] Aldrich) according to the supplier's recommendations. The sections were photographed using an epi-fluorescent microscope (ThermoFisher, EVOS M5000 Imaging System) and the photographs analyzed with image software (ImageJ) (Schneider, 2012). The results are presented in Table 2, showing the percentage increase in melanin levels compared to the untreated negative control and indirectly compared to the control treated with coconut oil without Tetradesmus obliquus extract.

[0109] Results: Table 2 Increase in melanin levels

[0110] [Tableaux2] Mean melanin level (% vs control) Standard deviation p-value (vs control) p-value (Binary comparison) Negative control (untreated) 100 4 / / Oily ingredient (Extract of T. obi iquus ex.la)) 1.5% 204 5 *** <0.001 **0.006 Coconut oil control (without extract) 172 7 *** <0.001 Positive control (Vitamin D3) 207 10 *** <0.001 /

[0111] Conclusion: At a dose of 1.5%, the oily ingredient comprising T. obliquus extract proved particularly effective in increasing melanin levels in (non-stressed) expiants, with an average increase in melanin levels almost similar to that observed in the presence of vitamin D3, known to stimulate melanin synthesis.

[0112] Outside of UV stress, T. obliquus extract has demonstrated its ability to increase melanin synthesis in expiants and can be used effectively as a pro-pigmenting active. Example 2c) In vivo study

[0113] Protocol: A double-blind, in vivo study was conducted on a population of 44 individuals aged 20 to 40 years with healthy skin, understood to mean skin not requiring therapeutic treatment as defined in the present invention, and without pigmentation spots on the evaluated body and facial areas. For a period of 56 days, a cream containing the oily ingredient including T. obliquus extract as described in Example 1a) or the same cream containing the oily ingredient without T. obliquus extract (coconut oil) ('placebo cream') was applied twice daily (morning and evening) every day to the entire body and face, avoiding the eye area. The cream was not rinsed off. Exclusion criteria included: - Treatment for a chronic disease, particularly based on oral or injectable corticosteroids; - An inflammatory reaction or a viral or bacterial infection during the 2 months before the start of the trial; - A pathology of the immune system or connective tissues; - A skin condition such as atopic dermatitis, rosacea, psoriasis, vitiligo. - Having ingested or having applied topically to the skin a self-tanning or whitening product.

[0114] Measurements of melanin levels, cortisol levels (Example 4), and pigmentation uniformity were performed at time points T0 (first day of the study), T56 days, and T56+1 on the abdomen. Melanin levels (index) were measured using a chromameter on the abdomen of all 44 subjects. individuals (CR-400 Chromameter) (L* parameter evaluation) and by colorimetry (SkinColorCatch) as follows:

[0115] Measurement of the pigmentation index via colorimetry (SkinColorCatch): A white LED bulb equivalent to daylight was applied to the skin via the colorimeter at a 45° angle to eliminate any glare. A measurement was taken at 6 separate locations on the abdomen (3 on the left side and 3 on the right). The results are presented in Tables 4 and 5.

[0116] Measurement of the pigmentation index and pigmentation homogeneity using a chromameter: the chromameter quantifies the chromatic properties of the skin by measuring three color-related parameters (L*, a**, and b*) (L* corresponds to luminance, i.e., the amount of light reflected by the skin; a** measures the position of the color on the red-green axis of the CIELAB coordinate system – positive values ​​a+ indicating red and negative values ​​a- indicating green-; and b* measures the position of the color on the yellow-blue axis of the CIELAB coordinate system – positive values ​​b+ indicating yellow and vice versa blue). The chromametric measurement is performed perpendicular to the skin axis.

[0117] A decrease in luminance L* indicates an increase in skin pigmentation. The results are presented in Table 3 (Statistics Table 4).

[0118] In parallel, a measurement of the luminance parameter L* was performed on the left and right sides of the abdomen of the study population in vivo at times T0 and T56 days. A non-significant difference in the measurement of the parameter L* between the left and right sides over time indicates the maintenance of homogeneity of skin pigmentation, and therefore of complexion. The results are presented in Table 6.

[0119] Results'.

[0120] Table 3 Pigmentation index by colorimetry

[0121] [Tables3] T0 T56 Cream containing the oily ingredient (Extract of T. obliqu us according to ex.la) 100 101.58* (p = 0.027) Placebo cream 100 100.7* (p = 0.040)

[0122] *2-way ANOVA statistical test

[0123] Table 4: Comparison of the pigmentation index between the 2 population groups (the one treated with the cream containing the extract vs the one containing the placebo cream) by statistical analysis (Mann-Whitney test):

[0124] [Tables4] Oily ingredient vs. placebo p-value Significance % change T56 / T0 0.0361 s +2.25%

[0125] (s: significant)

[0126] Conclusion: An increase of more than 2% in the melanin index was measured in the population receiving the cream containing the oily ingredient according to the invention, compared to the melanin index measured in the population receiving the placebo cream (without the extract). The oily ingredient containing the Tetradesmus obliquus extract is therefore effective in vivo in increasing skin pigmentation.

[0127] Table 5 Pigmentation index by chromametry

[0128] [Tables5] L* T0 L* T56 Cream including the oily ingredient (Extract of T. obliquus according to ex.la) 100 97.32 (-2.68%) *0.0003 Placebo cream (without extract) 100 99.74 (ns)

[0129] *p-value; ns: not significant

[0130] Conclusion: A decrease in the luminance parameter L* indicates an increase in the skin pigmentation index. Thus, luminance L* decreased significantly at time T56 days, by more than 2.5% in the population that received the T. obliquus extract. The T. obliquus extract and the oily ingredient containing it are therefore effective in increasing skin pigmentation.

[0131] Table 6 Measurement of skin tone homogeneity during pigmentation (Luminance difference L* between the left and right parts of the abdomen) (DIFF MO Y)

[0132] [Tableauxô] DIFFM OY (T0) Typical Deviation (SD) DIFFM OY (T5 6) Typical Deviation (SD) Cream including the oily ingredient (Extract of T. obliquus according to ex.la) 1.07 0.87 0.68 (ns) 0.84 Placebo cream (without extract) 0.94 0.72 0.96 0.76

[0133] Conclusion: The difference between the luminance (L*) measured on the left and right sides of the abdomen in the in vivo study population, after 56 days, was not significantly altered despite daily topical application of the cream containing the pigmenting oil ingredient according to the invention. Thus, after 2 months of daily topical application of said ingredient, the skin has been pigmented evenly. The crude extract of T. obliquus and the oily ingredient containing it are therefore effective in maintaining the evenness of skin tone.

[0134] Example 3: Skin preparation for tanning: maintaining skin pigmentation (evenness of complexion), even under conditions of exposure to UV-A;

[0135] Protocol: The protocol for measuring the skin pigmentation index by chromametry (Luminance L*) is that described in Example 2c) in the context of the in vivo study. At time T56, the abdomens of the population were exposed to UV-A rays for a period of 25 min in order to evaluate at time T56+1 (i.e. T57) the effects of the oily ingredient according to the invention on pigmentation, after exposure to UV-A (Table 7).

[0136] Table 7: Maintenance of pigmentation index after exposure to UV-A rays (Luminance L*).

[0137] [Tables7] L* T56 L* T57 Cream containing the oily ingredient (Extract of T. obliquus according to ex.la) 100 99.46 (ns) (-0.54%) Placebo cream (without extract) 100 98.44* (-1.55%)

[0138] (*p-value = 0.0027 Student's t-test)

[0139] Conclusion: After one day of exposure to UV-A rays, the luminance measured by chromametry in the group receiving the cream containing the oily ingredient according to the invention was not significantly altered, while the luminance (L*) decreased by 1.55% in the group receiving the placebo cream (MCT coconut oil), indicating an increase in pigmentation in this control group. The oily ingredient containing the T. obliquus extract according to the invention therefore has the ability to maintain skin pigmentation under UV light and prepares the skin for tanning.

[0140] Example 4: Relaxing effect of the oily ingredient comprising the extract of T. obliquus according to the invention: in vivo reduction of cortisol content (described as the stress hormone).

[0141] It is also known that sunlight has a beneficial effect on people's mood, making them feel more relaxed (less stressed), with an overall feeling of well-being. Therefore, we sought to demonstrate whether the oily extract according to the invention, applied to the skin, could confer this relaxing and well-being effect after application to the skin, without sun exposure (the oily extract would thus have a mimetic effect of the sun, of overall well-being).

[0142] Protocol: The in vivo study protocol is that described in Examples 2c) and 3. At times T0 and T56, saliva samples (approximately µL) were collected and then frozen at -20°C. An ELISA assay was performed on these samples. A spectrophotometer reading (450 nm) was taken for each sample. The results are expressed as the mean percentage (MOY) (n = 19 for the population receiving the cream containing the oily ingredient; n = 22 for the population receiving the placebo cream). Results#: Table 8

[0143] [Tables8] Cortisol (MO Y in %) 10 Cortisol (AVERAGE in %) 156 Cream containing the oily ingredient (T. obliquus extract according to ex.la) 100 45.83* Placebo cream (without extract) 100 74.18**

[0144] * p=0.041 ; **p=0.00527 (Student's t-test)

[0145] Conclusion: The oily ingredient demonstrated its ability to decrease the average cortisol level by more than 50%, unlike the population group that received topical application of the placebo cream, whose average measured cortisol level decreased by only 25%. The oily ingredient, including the T. obliquas extract, therefore promotes well-being and relaxation.

[0146] Example 5: Increased protection against UV rays (Solar Protection Filter booster activity, also known as 'SPF booster effect')

[0147] Protocol: An in vitro test based on ISO 24443 2021 relating to the in vitro determination of the sun protection factor (“SPF”) reflecting the level of protection against UV-B, and of UVA protection, was carried out as follows: a quantity of 30mg of organic or mineral base whose compositions are given in examples 7d) and 7e) and comprising the oily ingredient comprising the extract of T. obliquas as described in example la) (1.5% or 3%) or MCT oil (1.5% or 3%) as a control, was applied to the rough face of the sandblasted polymethyl methacrylate (PMMA) plates (1.2mg / cm2), with a bare finger pre-saturated with the bases in order to obtain the most homogeneous film possible. Measurements were then carried out by UV-2600 spectrophotometry (Shimatzu) or Lambda 1050+ (PerkinElmer) equipped with an integrating sphere between 290nm and 400nm.

[0148] The average of the absorbances read was carried out in order to obtain the SPF and UVA sun protection indices (Table 9) according to the calculations established by the ISO 24443 2021 standard (https: / / www.iso.org / fr / standard / 75059.html#:~:text=R%C3%A9sum%C3%A9.protection%20UVA%20de%20fa%C3%A7on%20reproducible): • The average SPF index (SPF / nv / ,ro) is obtained as follows: the spectrum of the standard UV solar radiation source (UV-SSR source) (S(X)) is multiplied by the sensitivity value of the corresponding erythematous action spectrum (E(X)) at that wavelength to obtain the effective solar burn energy at that wavelength. The resulting effective solar burn irradiance is integrated over the wavelength range of 290 to 400 nm. The sunscreen transmission values ​​at each wavelength are multiplied by the effective erythemal energy at that wavelength and integrated over the same interval to obtain the effective erythemal energy transmitted through the test. The ratio of these two integrals corresponds to the SPF / nv / 7ra value. • The PFUV A index (Average UVA Index in Table 9) is calculated in the same way as for the SPF,nvilm index: the intensity spectrum of the UVA radiation source (L(X)) (xenon arc lamp) is multiplied at each wavelength by the value of the action spectrum of the Persistent Pigment Darkening (PDD) and by the wavelength range (d(X) = Inm). The resulting effective irradiance is integrated over the wavelength range from 320 nm to 400 nm. The same calculation is performed, incorporating the average transmission of the oily ingredient layer or MCT oil as a spread control as described previously (T(X)). The resulting irradiance is integrated over the range from 320 to 400 nm. The ratio of the two integrals corresponds to the PFUV A index.

[0149] Calculations:

[0150] [Math.l] | EX). S(Al d(A) | S(A).TU). (U

[0151] [Math.2] ! P(AlLUld(X) / IP(A).UA).T(À).d(A) PFUV A-

[0152] Where E(X) is the erythematous action spectrum, S(X) is the standard solar spectrum, T(X) is the average transmission of the oily ingredient or spread MCT oil, d(X) is the wavelength range (Inm), P(X) is the action spectrum of the persistent darkening pigment (PPD), L(X) is the spectrum of the UVA radiation source (Xenon arc lamp).

[0153] The average SPF index and the average UVA index are expressed as a percentage relative to the control corresponding to the organic or mineral base.

[0154] Results: Table 9

[0155] [Tables9] Average SPF Index Average UVA Index n Control (organic base) 100 100 Organic base +1.5% Oily ingredient (e.g., la) 107 105 Organic base +3% Oily ingredient (e.g., la) 158 164 Control (mineral base) 100 100 Mineral base +1.5% Oily ingredient (e.g., la) 127 121 Mineral base +3% Oily ingredient (e.g., la) 164 144

[0156] Conclusion: The oily ingredient comprising the T. obliquus extract according to the invention increased the SPF and UVA protection ratings of organic and mineral sunscreens. For mineral filters, the SPF rating increased by 27% at a concentration of 1.5% and by 64% at a concentration of 3%, while the UVA rating increased by at least 21% at a concentration of 1.5%. For organic filters, the SPF rating increased by 7% at a concentration of 1.5% of the oily ingredient according to the invention and by 58% at a concentration of 3%. Similarly, the UVA rating increased by 5% and 64%, respectively, at a concentration of 3% of the oily ingredient.The oily ingredient containing Tetradesmus obliquus extract is therefore effective in increasing the protective effect provided by the sunscreens present in mineral and organic sunscreen bases (it is said to act as an 'SPF booster') and can be effectively incorporated into a cosmetic sunscreen composition. Due to its 'SPF booster' effect, the use of the oily ingredient according to the invention thus makes it possible to reduce the amount of sunscreens in the composition for an equivalent effect.

[0157] Example 6: Protection of the skin against the effects of UV rays: reduction of UV-induced inflammation

[0158] Since the level of interleukin IL-8 in the stratum corneum is an indicator of local inflammation, IL-8 levels were measured as part of the in vivo study described above, as follows: at times T56 and T57 after UV-A exposure, skin samples were collected using patches (D-SQUAM patches, CuDerm) from the abdomen of the two population groups being monitored. Three patches were successively applied to the same area of ​​skin and placed in PBS buffer. After sonication for 10 minutes, the skin cells were centrifuged. Proteins were extracted from the supernatant with Tris-HCl buffer (pH 7.6) containing Triton X-100 (0.1% v / v). The amount of protein was measured by a colorimetric assay (bicinchoninic acid BCA assay). IL8 levels were measured by ELISA assay and spectrophotometry (450nm) (Table 10).

[0159] Table 10: Maintenance of interleukin IL-8 levels after UV-A exposure

[0160] [Tables10] [IL-8] average (%) T56 [IL-8] average (%) T57 Cream including the oily ingredient (T. obliquus extract according to ex.la) 100 93.85 Placebo cream (without extract) 100 136.68*

[0161] *Student's test: p-value = 0.0116

[0162] Conclusion – IL-8 levels did not significantly change between T56 and T57 in the group receiving the cream containing the oily ingredient according to the invention. In contrast, IL-8 levels increased significantly by more than 36% in just 1 day after UV-A exposure in the group receiving the placebo cream. The oily ingredient containing T. obliquus extract therefore reduces inflammation induced by UV-A rays. The oily ingredient thus helps to reduce skin disorders related to UV rays, and in particular the effects of photoaging.

[0163] Example 7: Formulations comprising an extract of Tetradesmus obliquus

[0164] The formulations are prepared by mixing the various ingredients using techniques well known to those skilled in the art until a homogeneous mixture is obtained. The percentages are expressed as a percentage of the total weight of the composition (w / w). Example 7a) Body balm#:

[0165] [Tableauxll] Ingredients % by weight Water q.s.p. 100; Humectant 6.00-12.00; Gelling agent 0.50-1.75; Emulsifying agent 2.00-5.00; Oil phase 10.00-15.00; Consistency agent 1.50-3.00; Antioxidant 0.10-1.00; Perfume 0.10-1.00; pH regulator 0.05-2.00; Oily ingredient including an extract of T. obliquus (e.g., la) 1.50

[0166] When applied to the body, this balm has the ability to increase skin pigmentation, while promoting an even complexion.

[0167] Example 7b) Mist comprising solar filters:

[0168] [Tables 12] Ingredients % by weight Water q.s.p. 100 Gelling agent 1.00-2.50 Emulsifying agent 1.00-4.00 Sequestering agent 0.10-0.80 Oil phase 12.00-17.00 Sunscreens 8.00-13.00 Antioxidant 0.10-1.00 Fragrance 0.10-1.00 pH regulator 0.05-2.00 Oily ingredient including an extract of T. obliquus (e.g., la) 1.00-2.50

[0169] Applied to the face or body, this mist helps protect the skin from UV rays by filtering them.

[0170] Example 7c) Nutraceutical composition in capsule form:

[0171] [Tables 13] Ingredients % by weight Hydroxypropylmethylcellulose 11 Oily ingredient comprising an extract of T. obliquus (example la) 20-50 Maltodextrin 20-50 Acacia gum 10 Microcellulose 5-10 Magnesium stearate 2-5 Silicon dioxide 2-5

[0172] This composition, administered orally to a subject, prepares their skin for tanning. It can also be administered in combination with a sun protection composition (commercial sunscreen) containing UV filters, thereby boosting the sun protection provided by the UV filters contained in the sunscreen.

[0173] Example 7d): Organic sunscreen (Organic base used in Example 5)

[0174] [Tables 14] Ingredients % by weight Diethylamino-Hydroxybenzoyl hexyl benzoate 5.00 Bis-Ethylhexyloxyphenol 4.00 Ethylhexyl triazone 3.00 Diisopropyl adipate and propylene glycol dicaprylate / dicaprate 9.00 Dibutyl adipate 3.00 C20-22 Alkyl Phosphate 2.00 Cetearyl alcohol 3.00 Disodium EDTA 0.10 Water q.s.p. 100 Triethanolamine 1.00 Acacia gum 0.30 Glycerin 5.00 1,3-Propanediol 3.00 1,2-Hexanediol 0.50 O-cymen-5-ol 0.10 Oily ingredient comprising an extract of T. obliquas (example la) Or MCT oil 1.5 or 3

[0175] Example 7e): Mineral sunscreen (Mineral base used in example 5)

[0176] [Tables 15] Ingredients % by weight Zinc oxide, polyhydrostearic acid, caprylic / capric triglycerides 10.00 Titanium dioxide and caprylic / capric triglycerides and jojoba esters, polyhydrostearic acid and stearic acid 20.00 Cetearyl alcohol and coco glucoside 2.00 Diisopropyl adipate and propylene glycol dicaprylate / dicaprate and C12-C15 alkylbenzoate and diisopropyl sebacate 9.00 Dibutyl adipate 3.00 C20-22 Alkyl Phosphate and C20-22 alcohols 2.00 Cetearic alcohol 3.00 Disodium EDTA 0.10 Water q.s. 100 Triethanolamine 1.00 Oramix CGI 10 0.50 Acacia gum and gum Xanthan gum 0.30 Glycerin 5.00 1,3-propanediol 3.00 1,2-hexanediol 0.50 Oily ingredient including an extract of T. obliquus (example la) Or MCT oil 1.5 or 3

Claims

Demands

1. Cosmetic use of an extract of Tetradesmus obliquas or an oily ingredient comprising it to increase the pigmentation of healthy skin and / or healthy hair, advantageously of healthy hair, and / or to maintain the homogeneity of the complexion of healthy skin and / or to prepare healthy skin for tanning, and / or to promote relaxation and well-being of a healthy subject, apart from any exposure to UV.

2. Cosmetic use according to claim 1, characterized in that the extract is obtained by extraction in a solvent or mixture of solvents selected from water, acetone, butanone, hexane, ethyl acetate, methyltetrahydrofuran, 2-methyloxolane, heptane, an alcohol selected from ethanol, methanol, isopropanol, a natural or branched oil, a glycol, a polyol, an alcohol / water mixture, or glycol / water in a proportion of 99 / 1 to 1 / 99 (w / v), or by supercritical CO2 extraction.

3. Cosmetic use according to claim 1 or claim 2, characterized in that the extract is obtained by extraction in ethanol as the sole solvent.

4. Cosmetic use according to any one of claims 1 to 3, characterized in that the Tetradesmus obliquus extract is included in an oily ingredient comprising: - From 0.5% to 5% by weight, more advantageously from 0.5% to 3.5% by weight of Tetradesmus obliquus extract relative to the total weight of the oily ingredient, - From 0.05% to 1% by weight of vitamin E relative to the total weight of the oily ingredient, more advantageously from 0.06% to 0.25% by weight, and - From 96% to 99.45% by weight of a vegetable oil, preferably a medium-chain triglyceride (MCT) oil and more preferably coconut oil, relative to the total weight of the oily ingredient.

5. A cosmetic composition for topical application to the skin and / or its appendages comprising, in a physiologically acceptable medium: (i) an oily ingredient comprising: - From 0.5% to 5% by weight, or more advantageously from 0.5% to 3.5% by weight of Tetradesmus obliquas extract relative to the total weight of the oily ingredient, - From 0.05% to 1% by weight of vitamin E relative to the total weight of the oily ingredient, or more advantageously from 0.06% to 0.25% by weight, and - From 96% to 99.45% by weight of a vegetable oil, preferably a medium-chain triglyceride (MCT) oil and more preferably coconut oil, relative to the total weight of the oily ingredient and (ii) optionally in addition at least one cosmetically acceptable excipient chosen in particular from additional oils such as vegetable oils, in particular argan oil, shea oil, jojoba oil, avocado oil, sweet almond oil, or any oil extracted from a plant or a algae, including microalgae, specifically chosen from olive oil, rapeseed oil, linseed oil, sunflower oil,Medium-chain triglyceride (MCT) oils, C11-C13 alkanes, ester oils and mixtures thereof, preservatives, emulsifiers, emollients, surfactants, moisturizers, thickeners, gloss enhancers, texturizing agents, film-forming agents, organic or mineral sunscreens, pigments, colorants, perfumes, biological additives, chelating agents, astringents, polymers, reducing agents, pH regulators, humectants, conditioning agents, and mixtures thereof.

6. Cosmetic composition according to claim 5, characterized in that it further comprises at least one UV filter selected from an organic UV filter, an inorganic UV filter, and mixtures thereof.

7. Cosmetic composition according to claim 5 or claim 6, characterized in that the oily ingredient is present in said composition in a content ranging from 0.1% to 10% by weight, advantageously from 0.25% to 5% by weight, preferably even 1.5% by weight relative to the total weight of the composition.

8. A cosmetic composition according to any one of claims 5 to 7, characterized in that the cosmetic composition is in a form suitable for a topical application selected from a cream, a lotion, a gel, a soap, a spray, an oil, an oil-in-water or water-in-oil emulsion, an aerosol, a mousse, an ointment, a serum, a stick, a powder, a sunless tanning product, a dry shampoo, a shampoo, a hair coloring solution, a conditioner, a skin or hair mask, a leave-in hair treatment, a hairspray and a composition encapsulated in the form of spheres, microspheres or liposomes.

9. Nutraceutical use of an extract of Tetradesmus obliquus or an oily ingredient comprising it, to increase the pigmentation of healthy skin and / or healthy hair, advantageously of healthy hair, and / or to maintain the homogeneity of the complexion of healthy skin and / or to prepare healthy skin for tanning, and / or to promote relaxation and well-being of a healthy subject, apart from any exposure to UV.

10. Nutraceutical use according to claim 9, characterized in that the oily ingredient comprises: - From 8% to 79.85% by weight, advantageously from 20% to 50% by weight of Tetradesmus obliquus extract relative to the total weight of the oily ingredient, - From 0.15% to 1.25% by weight of vitamin E relative to the total weight of the oily ingredient, advantageously from 0.5% to 1% by weight, further advantageously from 0.5%, and - From 20% to 90% by weight and advantageously from 60% to 90% by weight of a vegetable oil, preferably a medium-chain triglyceride (MCT) oil and even more preferably coconut oil, relative to the total weight of the oily ingredient.

11. Nutraceutical use according to claim 10 characterized in that the oily ingredient is present in the nutraceutical composition in a content ranging from 10% to 70% by weight, advantageously ranging from 20% to 50% by weight relative to the total weight of the nutraceutical composition.

12. Nutraceutical use according to claim 11, characterized in that the nutraceutical composition is presented in a form suitable for oral administration selected in particular from a capsule, a softgel, a tablet, a lozenge, an orodispersible tablet, an orodispersible granule, a pill, a lozenge orodispersible, a soft capsule, a syrup, an ampoule, and a suspension.

13. A cosmetic or nutraceutical treatment method for healthy skin and / or its healthy appendages to increase the pigmentation of healthy skin and / or healthy appendages, advantageously of healthy hair, and / or to maintain the homogeneity of the complexion of healthy skin and / or to prepare healthy skin for tanning, and / or to promote relaxation and well-being in a healthy subject, apart from any UV exposure, comprising (i) the topical application to the skin and / or its appendages of an extract of Tetradesmus obliquas or an oily ingredient comprising it as defined in any one of claims 1 to 4, or of a cosmetic composition comprising it as defined in any one of claims 5 to 8,or (ii) the oral administration of an extract of Tetradesmus obliquus or an oily ingredient comprising it as defined in claim 10 or a nutraceutical composition comprising it as defined in claim 11 or claim 12.

14. A cosmetic treatment method according to claim 13, characterized in that the Tetradesmus obliquus extract, the oily ingredient comprising it or the cosmetic composition comprising said extract or said oily ingredient is applied topically to at least one area of ​​the body and / or face and / or hair, the body area being advantageously chosen from the décolleté, face, arms, shoulders, belly, legs and the hair being advantageously the hair.

15. An oily ingredient comprising an extract of Tetradesmus obliquus as defined in any one of claims 2 to 4 or claim 10, or a topical cosmetic composition as defined in any one of claims 5 to 8, or a nutraceutical composition as defined in claim 11 or 12, for use in the prevention and / or treatment of the adverse effects of UV radiation on the skin and / or its appendages.

16. Combination of an extract of Tetradesmus obliquus or an oily ingredient comprising it as defined in any one of claims 1 to 4 or claim 10, with at least one UV filter present in the same composition or in a distinct composition, as an agent to enhance the sun protection effect provided by the UV filter(s), for use in the prevention and / or treatment of the adverse effects of UV radiation on the skin and / or its appendages.