WO2019162468A1

WO2019162468A1 - Use of an essential oil of lemon savory for improving the biomechanical properties of the skin

Info

Publication number: WO2019162468A1
Application number: PCT/EP2019/054489
Authority: WO
Inventors: Marion GABANT; Corinne Ferraris
Original assignee: L'oreal
Priority date: 2018-02-23
Filing date: 2019-02-22
Publication date: 2019-08-29
Also published as: FR3078258A1; FR3078258B1

Abstract

The present invention relates to the cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the biomechanical properties of the skin.

Description

USE OF AN ESSENTIAL OIL OF LEMON SAVORY FOR IMPROVING THE

BIOMECHANICAL PROPERTIES OF THE SKIN

The present invention relates to the field of active agents that are capable of improving the biomechanical properties of the skin, especially the firmness, in particular for a cosmetic application.

The present invention relates to the field of active agents that are capable of improving the biomechanical properties of the skin, especially the firmness, in particular those associated with chronological ageing and photoageing.

The term "chronological ageing" means the age-related loss of firmness, and the term "photoageing" means a loss of firmness associated with exposure to UV.

The skin is the primary barrier for protecting the body from the external environment. Human skin consists of several compartments, three of which cover the whole of the body, namely a superficial compartment, which is the epidermis, the dermis and a deep compartment, which is the hypodermis. The cohesion of the dermis is provided by the dermo-epidermal junction.

Natural human epidermis is constituted mainly of three types of cells, namely keratinocytes, which form the vast majority, melanocytes and Langerhans cells.

The epidermis is conventionally divided into a basal layer of keratinocytes constituting the germinative layer of the epidermis, a“spinous” layer constituted of several layers of polyhedral cells positioned on the germinative layers, one to three "granular" layers and finally the comified layer (or stratum corneum ), constituted of a set of layers of keratinocytes at the terminal stage of their differentiation, known as comeocytes. Comeocytes are anuclear cells mainly composed of a fibrous matrix containing cytokeratins, surrounded by a very strong structure 15 nm thick, known as the comified envelope. The stacking of these comeocytes constitutes the comified layer which is responsible for the barrier function of the epidermis. In the course of the normal desquamation process, the most superficial comeocytes detach from the surface of the epidermis.

The dermis provides the skin with a solid support. It is also its nourishing element. It is constituted mainly of fibroblasts and an extracellular matrix, which is itself composed mainly of collagen, elastin and a substance known as ground substance, these components being synthesized by the fibroblasts.

As regards the dermo-epidermal junction (DEJ) or basal membrane, it is constituted of leaflets of extracellular matrix separating cells of different origin: keratinocytes and fibroblasts.

Collagen fibres are constituted of fibrils sealed to each other, thus forming more than ten different types of structures. Collagen fibres contribute to the elasticity, firmness and tonicity of the skin and/or the mucous membranes.

Collagen fibres are under constant renewal, but this renewal decreases with age, which leads to thinning of the dermis and flattening of the DEJ. This thinning of the dermis may also be due to pathological causes, for instance hypersecretion of corticoid hormones, certain pathological conditions, or else vitamin deficiencies (the case of vitamin C in scurvy). It is also accepted that extrinsic factors such as ultraviolet radiation, smoking or certain treatments (glucocorticoids, vitamin D and derivatives, for example) also have an effect on the skin and on its collagen content.

Various factors lead to collagen degradation, with all the consequences that may be envisaged for the structure and/or firmness of the skin and/or the mucous membranes.

In general, the loss of skin elasticity may be the consequence of modifications in the network of dermal elastic fibres containing fibrillin.

In terms of biological mechanism, wrinkles may also result from a loss of muscle or from repeated muscular tensions, from a loss of fat tissue, from persistent gravitational forces and from loss of bone and cartilage in the face. Flattening of the junction between the dermis and the epidermis and the reduction of collagen IV are considered to be factors which influence the formation of wrinkles. From a histological viewpoint, the epidermis appears atrophied, which is a manifestation different from ptosis of the skin tissues observed during loss of skin elasticity.

Admittedly, active agents have already been reported for their properties with regard to maintaining or re-establishing the biomechanical properties of the skin.

By way of example, vitamin C (or ascorbic acid) is known to stimulate collagen synthesis by preventing, as cofactor, the auto -inactivation of lysine- and proline- hydroxylase enzymes and by increasing the synthesis of procollagen mRNAs. Ascorbic acid (or vitamin C) is also known for stimulating elastin synthesis in the skin, or for treating wrinkles.

Also, WO2014/173712 teaches deodorant properties of an essential oil of Satureja Montana. FR3004939 teaches properties against greasy skin; FR3004938 reports anti-dandruff properties; BE1016041 teaches anti-hair loss effetcs and EP0433132 teaches anti-bacterial and anti-fimgal effects.

There nevertheless remains a need to improve the biomechanical properties of the skin, especially the firmness, for preventing and combating the loss of firmness of the skin associated with chronological ageing and photoageing, and for preserving the quality of the skin.

The need also remains to maintain the functions of the epidermis, and thus to slow down the cutaneous signs associated with chronological ageing and photoageing, and in particular to maintain the epidermal renewal.

The object of the present invention is to meet these needs.

DESCRIPTION OF THE INVENTION

The present invention describes cosmetic compositions containing at least one essential oil of lemon savory for improving the biomechanical properties of the skin, and especially the firmness of the skin; which also includes the cutaneous signs associated with impairment of said biomechanical properties.

The term "skin" means the entire skin of the body, including the scalp, mucous membranes and semi-mucous membranes. More particularly, in the present invention, the skin of the neckline, of the neck and of the face, and especially the skin of the face, and also the skin of the hands and feet, and the scalp, are considered.

The present invention also describes cosmetic compositions containing at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, for improving epidermal renewal for better skin quality.

Also, the use is disclosed herein of an essential oil of lemon savory as an active agent for overcoming and/or preventing impairment of the biomechanical properties of the skin and thus the manifestation of skin disorders directly associated with such impairment, for instance, among the associated disorders, thinning of the dermis and/or degradation of the collagen fibres, this latter consequence leading to the appearance of flabby, flaccid and/or wrinkled skin, combating which being precisely the aim of the present invention.

Surprisingly, the inventors have in effect demonstrated that an essential oil of lemon savory has an influence on the expression of several cellular markers associated with the mechanical properties of the skin.

Surprisingly also, the particular properties of the essential oil of lemon savory are also more pronounced than those of the essential oil of winter savory.

Thus, an essential oil of lemon savory may be used as an active agent for treating and/or preventing the signs associated with impairment of the biomechanical properties of the skin. These properties are particularly advantageous for treating and/or preventing loss of firmness of the skin.

The term " improving the biomechanical properties of the skin " also means " maintaining and/or restoring the biomechanical properties of the skin ", which includes " treating and/or preventing impairment of the biomechanical properties of the skin " associated with chronological ageing and photoageing.

According to the invention, the term " prevent " or "prevention" means reducing the probability of occurrence or reducing a risk of manifestation of the phenomenon concerned.

An essential oil according to the invention, or a cosmetic composition comprising said essential oil, makes it possible even more particularly to maintain and/or restore the tonicity, firmness, suppleness and/or density properties of the skin.

Thus, according to a first aspect, the invention relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the biomechanical properties of the skin associated with chronological ageing and photoageing.

According to a second aspect, the invention relates to a cosmetic process comprising a step consisting in applying at least one essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora, and most particularly Satureja Montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the biomechanical properties of the skin.

Particular indications

The term "bioMechanical properties of the skin" means the elasticity, tonicity, firmness and/or density properties of the skin.

The term " cutaneous signs" means any modification in the external appearance of the skin, for instance wrinkles, especially around the eyes and at the comers of the mouth, fine lines, wizened skin, flabby skin, flaccid skin, thinned skin, bags under the eyes, skin furrows, a lack of elasticity and/or tonicity of the skin, but also any internal modification of the skin that is not automatically reflected by a modified outer appearance, for instance any internal degradation of the skin, particularly of the collagen fibres, following exposure to ultraviolet radiation.

For the purposes of the invention, the term "cutaneous signs of ageing" in particular means any change in the external appearance of the skin due to ageing, whether it be chronobio logical and/or photo-induced ageing, for instance wrinkles and fine lines, wizened skin, flabby skin, thinned skin, lack of elasticity and/or tonicity of the skin, lack of density and/or firmness of the skin, but also any internal modification of the skin that is not automatically reflected by a modified outer appearance, for instance any internal degradation of the skin, particularly of collagen, following exposure to ultraviolet radiation.

ln particular, the invention is directed towards a cosmetic use of at least one essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora, and most particularly Satureja Montana ssp. variegata or citriodora, or of a cosmetic composition comprising said essential oil, as an active agent for treating and/or preventing the signs associated with impairment of the biomechanical properties of the skin; this includes the treatment and/or prevention of the associated cutaneous signs, and most particularly the cutaneous signs of ageing, whether they be chronological or photo-induced.

Thus, according to one embodiment, the invention is also directed towards a cosmetic use, characterized in that said essential oil or said composition are used for treating or preventing the cosmetic signs associated with ageing of the skin, in particular related to age or to exposure to sunlight.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for maintaining and/or restoring the tonicity, firmness, elasticity and/or density properties of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the tonicity, firmness, elasticity and/or density properties of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for maintaining and/or restoring the tonicity of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the tonicity of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for maintaining and/or restoring the firmness of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja Montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the firmness of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for maintaining and/or restoring the elasticity of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the elasticity of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for maintaining and/or restoring the density of the skin.

According to one embodiment, the invention thus relates to a cosmetic use of at least one essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the density of the skin.

Said cosmetic indications are also applicable to a cosmetic process according to the invention, comprising a step consisting in applying an essential oil of lemon savory, in particular Satureja montana L. ssp. citriodora, and most particularly Satureja montana ssp. variegata or citriodora, or a cosmetic composition comprising said essential oil, as an active agent for improving the biomechanical properties of the skin.

Essential oil

Essential oils are products obtained from starting materials of plant origin (leaves, stems, flowers, roots, bark, fruit or whole plant, for example). According to the definition given in the international standard ISO 9235 and adopted by the Commission of the European Pharmacopoeia, an essential oil is an odorous product generally of complex composition, obtained from a botanically defined plant raw material, either by steam distillation, or by dry distillation, or via an appropriate mechanical process without heating (cold pressing). The essential oil is generally separated from the aqueous phase via a physical process which does not result in any significant change in the composition.

Essential oils are generally volatile and liquid at room temperature, which distinguishes them from“set” oils. They are more or less coloured and their density is generally less than that of water. They often have a high refractive index. They are liposoluble and soluble in the usual organic solvents, distillable with steam, and very sparingly soluble in water.

The choice of the technique for obtaining an essential oil depends mainly on the starting material: its original state and its characteristics, its intrinsic nature. The “essential oil/plant starting material” yield may be extremely variable depending on the plants: 15 ppm to more than 20%. The choice of the production technique determines the characteristics of the essential oil, in particular viscosity, colour, solubility, volatility, and richness or poorness in certain constituents.

Among the methods for obtaining an essential oil, mention may be made of steam distillation, which may be performed, for example, by dry distillation or hydrodistillation. Hydrodistillation may be performed on glass apparatus, such as that defined in the European Pharmacopoeia for the determination of the essential oil from a plant material. Steam distillation corresponds to vaporization, in the presence of steam, of a sparingly water-miscible substance. The raw material is placed in contact with water brought to the boiling point (hydrodistillation) or with steam in a still pot (dry distillation). The steam entrains the essential oil vapour, which is condensed in the condenser and recovered as a liquid phase in a Florentine vase (or essence jar), where the essential oil is separated from the water by settling. The aqueous distillate that remains after the steam distillation, once the separation of the essential oil has been performed, is known as the “aromatic water” or“hydrolate” or“distilled floral water”.

The essential oil in accordance with the invention may be prepared according to the techniques mentioned above and will preferably be obtained according to the standard technique of steam distillation. Steam distillation corresponds to vaporization, in the presence of steam, of a sparingly water-miscible substance. The raw material is placed in contact with steam in a still pot. The steam entrains the essential oil vapour, which is condensed in the condenser and recovered as a liquid phase in a Florentine vase (or essence jar), where the essential oil is separated from the water by settling. The aqueous distillate that remains after the steam distillation, once the separation of the essential oil has been performed, is known as the “aromatic water” or“hydrolate” or“floral water” or even“distilled floral water”.

The essential oil of lemon savory, a plant characteristic of the Vercors region of France and the Alps, is obtained after steam distillation of the floral aerial parts of the plant. Moreover, harvesting may be performed at various stages of cutting: beginning of flowering to end of flowering and preferably at the full bloom stage.

An essential oil of lemon savory that is suitable for use in the invention may thus be obtained by extraction of the plant and of the flowers by steam distillation.

According to a particular form of the invention, the essential oil of lemon savory that is suitable for use in the invention is obtained by extraction of the aerial parts of the plant, which is preferentially in bloom, by steam distillation.

The chemical composition of the essential oil of lemon savory in accordance with the invention thus obtained may be analysed by conventional techniques known to those skilled in the art, such as gas chromatography GC analysis, chromatographic analysis with flame ionization detection, referred to as GC-FID, or GC/MS analysis, which consists in the use of a mass spectrometer coupled to a gas chromatograph. Thus, the main components of this essential oil are: geraniol, t-P-carophyllene, nerol, germacrene D, b-bisabolene and geranial.

According to one embodiment, said composition may thus comprise, or even consist of, an essential oil of lemon savory comprising:

- at least 60% by weight of geraniol;

- at least 4% by weight of trans-P-carophyllene, preferably at least 5% by weight of trans-P-carophyllene; and

- at least 1% by weight of nerol, preferably at least 3% by weight of nerol; relative to the total weight of the essential oil. Thus, an essential oil of lemon savory may comprise at least 60% by weight of geraniol, which includes 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74% and 75% by weight of geraniol. Also, an essential oil of lemon savory ( Satureja Montana L. ssp. citriodora) may comprise at least 5% by weight of trans- b-carophyllene, which includes at least 5%, 6% and 7% by weight of trans-P-carophyllene.

Also, an essential oil of lemon savory may comprise at least 1% by weight of nerol, which includes at least 1%, 2%, 3%, 4% and 5% by weight of nerol, in particular at least 3% of nerol.

By way of example, an essential oil of lemon savory that is suitable for use in the invention may contain:

- at least 60% by weight of geraniol;

- at least 5% by weight of trans-P-carophyllene;

- between 1% and 5% by weight of nerol;

- between 1% and 5% by weight of germacrene D;

- between 0.5% and 5% by weight of b-bisabolene; and

- between 0.5% and 5% by weight of geranial.

According to a more particular embodiment, an essential oil of lemon savory that is suitable for use in the invention may contain:

- between 60% and 80% by weight of geraniol, in particular between 60% and

75%;

- between 5% and 15% by weight of trans-P-carophyllene;

- between 1% and 5% by weight of nerol;

- between 1% and 5% by weight of germacrene D;

- between 0.5% and 5% by weight of b-bisabolene; and

- between 0.5% and 5% by weight of geranial.

According to an even more particular embodiment, an essential oil of lemon savory that is suitable for use in the invention may contain:

- between 65% and 70% by weight of geraniol;

- between 6% and 10% by weight of trans-P-carophyllene; - between 1% and 5% by weight of nerol;

- between 1% and 5% by weight of germacrene D;

- between 0.5% and 4% by weight of b-bisabolene; and

- between 0.5% and 4% by weight of geranial.

The contents indicated herein are given relative to the total weight of the essential oil under consideration.

Hydro late

A hydrolate is a generally very dilute product obtained from a botanically defined plant raw material by steam distillation. The hydrolate (aqueous phase) is usually separated from the essential oil by means of a physical process that does not result in any significant change in the composition.

The hydrolate in accordance with the invention may preferably be prepared according to the conventional steam distillation technique.

Steam distillation corresponds to vaporization, in the presence of steam, of a sparingly water-miscible substance. The raw material is placed in contact with steam in a still pot. The steam entrains the essential oil vapour, which is condensed in the condenser and recovered as a liquid phase in a Florentine vase (or essence jar), where the essential oil is separated from the water by settling. The aqueous distillate which remains once the separation of the essential oil has been performed, generally by steam distillation, is known as the“ aromatic water” or“ hydrolate” or“floral water” or even“ distilled floral water”.

The hydrolate may be obtained from a whole plant, preferably a plant, a shrub or a flower, or from a part of this plant chosen from the flowers, leaves, stems, seeds, fruits, roots, petals, buds and bark, which may be in various states of dryness (dry, withered or fresh form), and mixtures thereof.

According to the invention, the hydrolate of lemon savory is preferentially obtained after steam distillation of the aerial parts of the plant that are in bloom, generally at a biomass/hydro late ratio of 1/1 and without cohobation, for approximately a period ranging from 30 min to 8 hours, preferably between 1 and 4 hours, more particularly between 1 and 2 hours, such as 1 h 30 min. The lemon savory hydrolate is a colourless water-soluble liquid with an aromatic, slightly herbaceous, fresh odour and a lemon note, containing a large amount of water, such as greater than 90%, in particular greater than 95%, more particularly greater than 98%.

The main organic component of the hydrolate is geraniol, which is present in a content of at least 0.03% by total weight of said hydrolate, in particular approximately 0.05% by weight, for example in a content of between 0.04% and 0.06%.

Besides geraniol, the other main organic components of the lemon savory hydrolate, according to the invention, are generally nerol, citral and l-octen-3-ol.

The contents indicated herein are given relative to the total weight of the hydrolate (extract) under consideration.

Compositions

When said essential oil of lemon savory is used in a composition, especially a cosmetic or dermatological composition, this essential oil may form a substantial, major or minor part of said composition.

Thus, according to certain embodiments, said composition may comprise less than 50% by weight of said essential oil, relative to the total weight of this composition. For example, said composition may comprise less than 40% by weight of said essential oil, especially less than 30% by weight of said essential oil, in particular less than 20% by weight of said essential oil, more particularly less than 10% by weight of said essential oil, or even less than 1% by weight of said essential oil.

For example, this composition may comprise less than 10% by weight of said essential oil, for example less than 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2% or less than 0.1%, by weight of said essential oil relative to the total weight of the composition.

Alternatively, this composition may comprise more than 10% by weight of said extract, by weight of said extract relative to the total weight of the composition.

According to other embodiments, said composition may comprise 30% or more than 30% by weight of said essential oil, for example, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, or more than 50% by weight, relative to the total weight of the composition. For example, this composition may comprise more than 60% by weight of said essential oil relative to the total weight of the composition, which includes more than 70%, more than 80%, or even more than 90% by weight, relative to the total weight of the composition.

According to a particular embodiment, a composition according to the invention may be characterized in that the essential oil, or the composition comprising said essential oil, comprises geraniol.

According to a particular embodiment, a composition according to the invention may be characterized in that the essential oil, or the composition comprising said essential oil, comprises geraniol, ί-b-caryophyllene, nerol, germacrene D, b-bisabolene and geranial.

According to certain embodiments, said composition comprising said essential oil may comprise at least one other essential oil and/or hydrolate such as lemon savory hydro late.

The compositions according to the invention may, where appropriate, comprise a mixture of essential oils and hydrolates.

For example, when a composition is a mixture of essential oil and of hydrolate, the essential oil of lemon savory may be in a volume excess relative to the hydrolate. Conversely, said hydrolate may be in a volume excess relative the essential oil.

In addition, the compositions according to the invention may, where appropriate, comprise essential oils or hydrolates other than those obtained from lemon savory. When the composition comprises an hydrolate of lemon savory, the composition may be characterized in that it comprises geraniol. In particular, when the composition comprises an hydrolate of lemon savory, the composition may be characterized in that it comprises geraniol, nerol, citral and l-octen-3-ol.

The compositions, especially cosmetic or dermatological compositions, which may be used in the context of the invention generally comprise a physiologically acceptable medium, preferably a cosmetically acceptable medium.

The term “physiologically acceptable medium” means a medium that is compatible with keratin materials and in particular the skin. The composition according to the invention may therefore comprise water and/or any adjuvant normally used in the envisaged field of application.

Mention may be made especially of organic solvents, especially Ci-C₆ alcohols and C2-C10 carboxylic acid esters; carbon-based and/or silicone oils, of mineral, animal and/or plant origin; water, waxes, pigments, fillers, dyes, surfactants, emulsifiers, coemulsifiers; cosmetic or dermatological active agents, UV-screening agents, polymers, hydrophilic or lipophilic gelling agents, thickeners, preserving agents, fragrances, bactericides, odour absorbers and antioxidants.

These optional adjuvants may be present in the composition in a proportion of from 0.001% to 80% by weight and in particular from 0.1% to 40% by weight relative to the total weight of the composition.

The aqueous phase (water and optionally the water-miscible solvent) may be present in the composition in a content ranging from 0.1% to 99.9% by weight, relative to the total weight of the composition, for example ranging from 40% to 95% by weight.

According to exemplary embodiments, the compositions of the invention may comprise an essential oil of lemon savory; and a pharmaceutically acceptable medium.

According to exemplary embodiments, the compositions of the invention may comprise an essential oil of lemon savory; at least one adjuvant, and a pharmaceutically acceptable medium.

The compositions according to the invention may be in any presentation form conventionally used for topical application and especially in the form of aqueous or aqueous-alcoholic solutions, oil-in-water (O/W), water-in-oil (W/O) or multiple (triple: W/O/W or O/W/O) emulsions, aqueous gels, or dispersions of a fatty phase in an aqueous phase using spherules, it being possible for these spherules to be lipid vesicles of ionic and/or nonionic type (liposomes, niosomes or oleosomes). These compositions are prepared according to the usual methods.

The compositions according to the invention may also be in anhydrous form, for instance in the form of an oil. The term " anhydrous composition " means a composition containing less than 1% by weight of water, or even less than 0.5% water, and especially free of water, the water not being added during the preparation of the composition but corresponding to the residual water provided by the mixed ingredients. Advantageously, the compositions according to the invention are in liquid or two-phase form, or in the form of a gel, an emulsion, a powder or a paste. In addition, the composition according to the invention may be more or less fluid and may have the appearance of a white or coloured cream, an ointment, a milk, a lotion, a serum, a paste, a foaming gel, a care product, a tonic or a foam. It may optionally be applied to the skin in aerosol form. It may also be in solid form, for example in stick form.

A composition according to the invention may comprise an oily phase especially comprising fatty substances other than the compounds present in an essential oil of lemon savory.

A composition used according to the invention may advantageously comprise at least one liquid fatty substance.

The term "liquid fatty substance " means a compound with a melting point below about 30-35°C, as opposed to solid fatty substances, such as waxes, which have a melting point above about 50°C.

When the composition used according to the invention includes an oily phase, the latter preferably contains at least one oil other than the compounds present in an essential oil according to the invention.

It may also contain other fatty substances. As oils that may be used in the composition of the invention, examples that may be mentioned include:

- hydrocarbon-based oils of animal origin, such as perhydrosqualene; hydrocarbon-based oils of plant origin, such as liquid triglycerides of fatty acids including from 4 to 10 carbon atoms, for instance heptanoic or octanoic acid triglycerides or alternatively, for example, sunflower oil, com oil, soybean oil, marrow oil, grapeseed oil, sesame oil, hazelnut oil, apricot oil, macadamia oil, arara oil, castor oil, avocado oil, caprylic/capric acid triglycerides, for instance those sold by the company Stearinerie Dubois or those sold under the names Miglyol 810, 812 and 818 by the company Dynamit Nobel, jojoba oil or shea butter oil; synthetic esters and synthetic ethers, especially of fatty acids, for instance oils of formulae R'C00R2 and R'0R2 in which R’ represents a fatty acid residue including from 8 to 29 carbon atoms and R2 represents a branched or unbranched hydrocarbon-based chain containing from 3 to 30 carbon atoms, for instance Purcellin oil, isononyl isononanoate, isopropyl myristate, 2-ethylhexyl palmitate, 2-octyldodecyl stearate, 2-octyldodecyl erucate or isostearyl isostearate; hydroxylated esters such as isostearyl lactate, octyl hydroxy stearate, octyldodecyl hydroxystearate, diisostearyl malate, triisocetyl citrate and fatty alkyl heptanoates, octanoates and decanoates; polyol esters, for instance propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters, for instance pentaerythrityl tetraisostearate;

- linear or branched hydrocarbons of mineral or synthetic origin, such as volatile or non-volatile liquid paraffins, and derivatives thereof, petroleum jelly, polydecenes, and hydrogenated polyisobutene such as Parleam oil;

- fatty alcohols containing from 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol and a mixture thereof (cetylstearyl alcohol), octyldodecanol, 2-butyloctanol, 2-hexyldecanol, 2-undecylpentadecanol, oleyl alcohol or linoleyl alcohol;

- partially hydrocarbon-based and/or silicone-based fluoro oils, such as those described in JP-A-2-295 912;

- silicone oils, such as volatile or non-volatile polymethylsiloxanes (PDMS) with a linear or cyclic silicone chain, which are liquid or pasty at room temperature, especially cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexasiloxane; polydimethylsiloxanes including alkyl, alkoxy or phenyl groups, which are pendent or at the end of a silicone chain, these groups containing from 2 to 24 carbon atoms; phenyl silicones, such as phenyl trimethicones, phenyl dimethicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyl dimethicones, diphenylmethyldiphenyltrisiloxanes or 2-phenylethyl trimethylsiloxy silicates, and polymethylphenylsiloxanes;

- mixtures thereof

In the list of the oils other than the compounds mentioned above, the term "hydrocarbon-based oil" means any oil predominantly including carbon and hydrogen atoms, and optionally ester, ether, fluoro, carboxylic acid and/or alcohol groups. The other fatty substances that may be present in the oily phase are, for example, fatty acids including from 8 to 30 carbon atoms, such as stearic acid, lauric acid, palmitic acid and oleic acid; waxes, such as lanolin wax, beeswax, camauba wax or candelilla wax, paraffin wax, lignite wax or microcrystalline waxes, ceresin or ozokerite, and synthetic waxes, such as polyethylene waxes and Fischer-Tropsch waxes; silicone resins such as trifluoromethyl- Ci_C₄-alkyl dimethicone and trifluoropropyl dimethicone; and silicone elastomers, such as the products sold under the name KSG by the company Shin-Etsu, under the name Trefil, BY29 or EPSX by the company Dow Coming, or under the name Gransil by the company Grant Industries. These fatty substances may be chosen in a varied manner by a person skilled in the art in order to prepare a composition having the desired properties, for example in terms of consistency or texture.

According to a particular embodiment of the invention, the composition according to the invention is a water-in-oil (W/O) or oil-in-water (O/W) emulsion. The proportion of the oily phase of the emulsion may range from 5% to 90% by weight and preferably from 5% to 60% by weight relative to the total weight of the composition. The emulsions generally contain at least one emulsifier chosen from amphoteric, anionic, cationic and nonionic emulsifiers, used alone or as a mixture, and optionally a coemulsifier. The emulsifiers are chosen in an appropriate manner according to the emulsion to be obtained (W/O or O/W emulsion). The emulsifier and the coemulsifier are generally present in the composition in a proportion ranging from 0.3% to 30% by weight and preferably from 0.5% to 20% by weight relative to the total weight of the composition.

For W/O emulsions, examples of emulsifiers that may be mentioned include dimethicone copolyols, such as the mixture of cyclomethicone and dimethicone copolyol sold under the name DC 5225 C by the company Dow Coming, and alkyl dimethicone copolyols such as the lauryl methicone copolyol sold under the name Dow Coming 5200 Formulation Aid by the company Dow Coming, and the cetyl dimethicone copolyol sold under the name Abil EM 90® by the company Goldschmidt. A crosslinked elastomeric solid organopolysiloxane including at least one oxyalkylenated group, such as those obtained according to the procedure of Examples 3, 4 and 8 of US-A-5 412 004 and of the examples of US-A-5 811 487, especially the product of Example 3 (synthetic example) of patent US-A-5 412 004, such as the product sold under the reference KSG 21 by the company Shin-Etsu, may also be used as surfactants for W/O emulsions.

For the O/W emulsions, examples of emulsifiers that may be mentioned include nonionic emulsifiers such as oxyalkylenated (more particularly polyoxyethylenated) fatty acid esters of glycerol; oxyalkylenated fatty acid esters of sorbitan; oxyalkylenated (oxyethylenated and/or oxypropylenated) fatty acid esters; oxyalkylenated (oxyethylenated and/or oxypropylenated) fatty alcohol ethers; sugar esters such as sucrose stearate; and mixtures thereof, such as the mixture of glyceryl stearate and PEG-40 stearate. The composition according to the invention may also contain adjuvants that are common in cosmetics, such as hydrophilic or lipophilic gelling agents, preserving agents, water, solvents, fragrances, fillers, waxes, pasty fatty substances, UV-screening agents, odour absorbers, dyestuffs, basic agents, acids, or nonionic, anionic or cationic surfactants. The amounts of these various adjuvants are those conventionally used in the field under consideration, for example from 0.01% to 20% of the total weight of the composition. Depending on their nature, these adjuvants may be introduced into the fatty phase, into the aqueous phase and/or into the lipid vesicles. The compositions according to the invention may also comprise at least one aqueous phase. The aqueous phase contains water and optionally other water-soluble or water-miscible organic solvents. An aqueous phase that is suitable for use in the invention may comprise, for example, a water chosen from a natural spring water, such as water from La Roche-Posay, water from Vittel or waters from Vichy, or a floral water such as the lemon savory hydro late.

Needless to say, a person skilled in the art will take care to select this or these optional additional ingredients and/or active agents, and/or the amount thereof, such that the advantageous properties of the essential oil of lemon savory according to the invention are not, or are not substantially, adversely affected by the envisaged addition.

In the context of the present invention, the term " additional active agent for caring for the skin" means a compound which, by itself, i.e. not requiring the involvement of an external agent to activate it, has a biological activity that is beneficial to the skin.

Said essential oil (or said composition comprising said essential oil) is used topically in the context of a use or of a process according to the invention. Thus, according to a particular embodiment, the invention relates to a use or a process in which said essential oil or said composition may be applied topically.

According to a particular embodiment, the invention thus also relates to an essential oil of lemon savory (or a cosmetic composition comprising said essential oil) intended to be applied topically.

According to a preferred embodiment, said essential oil (or said composition comprising said essential oil) is used topically.

The term“ topically” means application to the surface of the skin. The application of a composition comprising said essential oil may optionally be followed by a step of rinsing with water.

According to one embodiment, the application is repeated, for example 1 to 3 times daily for one or more days, preferably once or twice a day, and particularly over an extended period of at least 4 weeks, or even 4 to 15 weeks, with, where appropriate, one or more periods of stoppage.

The compositions according to the invention may be applied directly to the skin or, alternatively, to cosmetic supports of occlusive or non-occlusive type, intended to be applied locally to the skin. As non-limiting examples of cosmetic supports, mention may be made especially of a patch, a wipe, a roll-on and a pen.

According to a particular embodiment, the composition according to the present invention will comprise, besides an essential oil of lemon savory as defined above, at least one additional active agent for caring for the skin, such as elderly skin, dull skin, greasy skin or greasy-prone skin.

The composition may optionally be rinsed off after having been applied to the skin. Moreover, after the application of the composition according to the invention, a composition comprising one or more active agents may be applied to the surface of the skin.

According to a particular embodiment of the invention, other agents intended to make the appearance and/or texture of the skin more attractive may also be added to the composition that is suitable for use in the invention.

Advantageously, a composition according to the invention may comprise at least one UV-screening agent. This screening agent is chosen from UV-A and/or UV-B screening agents. Even more particularly, said UV-screening agent is chosen from water- soluble organic UV-screening agents, liposoluble organic screening agents, and mixtures thereof, and more particularly liposoluble organic UV-screening agents. EXAMPLES

Example 1:

Production of an essential oil of lemon savory

An essential oil of lemon savory was prepared from the aerial parts of the plant at the full bloom stage by distillation of 5 kg by fresh weight by steam distillation for 1 hour 30 minutes in a 50 litre distillation device. The volume of essential oil obtained was about 20 mL.

The essential oil obtained comprises, as major components (by weight relative to the total weight of the hydrolate):

- geraniol: 69% by weight;

- t-P-carophyllene: 9% by weight;

- nerol: 3% by weight;

- germacrene D: 4.5% by weight;

- b-bisabolene: 1.5% by weight;

- geranial: 2% by weight.

The composition of the essential oil obtained was determined by gas chromatography (GC) coupled to mass spectrometry.

Example 2: Demonstration of the anti-ageing effect of an essential oil of lemon savory obtained in Example 1.

A. Principle

The aim of this study is to evaluate the effects of the essential oil of lemon savory of Example 1 on epidermal or dermal markers modulated in the course of ageing by the immunohistochemistry technique.

Vitamin C is used as reference molecule (100 mM).

The essential oil is evaluated at 0.0001%.

The various markers studied on frozen slices are:

- epidermal marker: cytokeratin 10 - two dermal markers: collagen XII, fibrillin.

B. Materials & Methods

Reconstructed skin model

The skin model used is a REALSKIN® model such as the one described in the following studies:

- Tran et al. (“in vitro and in vivo studies with tetrahydrojasmonic acid (LR2412) reveal its potential to correct signs of skin ageing.”; J. Eur. Acad. Dermatol. VenereoL; 2014; 28(4): 415-23);

- Asselineau & Prunieras (“Reconstruction of ‘simplified’ skin: control of fabrication; 1984; Br. J. Dermatol. ,11 l(s27), 219-222).

The application of the active agents is performed in the culture medium at various concentrations: treatment in triplicate for measurement of the viability (reduction of MTT) for each condition; treatment in duplicate for the analysis of tissues in histology and immunohistochemistry. The products are diluted in ethanol.

The experiment is stopped after five days of treatment. Five days after treatments, the inserts are sliced and prepared for the histological treatment:

- one tissue half is fixed in a 4% W/V formaldehyde solution and then dehydrated, after which it is included in paraffin.

- the other half is coated in O.C.T. tissue and then frozen in liquid nitrogen.

C. Results

The results are all expressed as marked surface/epidermal length.

Table 1: influence of the active agent on the expression of markers in an epidermal model

The scores indicated are semi-quantitative for the epidermal marker (CK 10). The analysis is quantitative for the dermal marker (Col XII, marked surface in pmVlength of the epidermis in pm).

The essential oil of lemon savory tested at a concentration of 0.0001% has activity on the epidermis of differentiating type synonymous with renewal with localization of the cytokeratin 10 marker in the uppermost layers of the epidermis. At this concentration, the essential oil of lemon savory also stimulates the expression of the dermal marker collagen XII, acting on the biomechanical properties of fibrillin.

Vitamin C tested at 100 mM has an activity profile promoting matrix synthesis (effect observed for the markers collagen XII and fibrillin).

The markings show that the essential oil of lemon savory promotes epidermal renewal by limiting epidermal differentiation and promotes the synthesis of matrix molecules such as collagen XII and fibrillin, thus improving the mechanical properties of the skin.

- ^(l)Nishiyama et al. ("Type XII and XIV collagens mediate interactions between banded collagen fibers in vitro and may modulate extracellular matrix deformability", J. Biol. Chem. 1994 Nov 11; 269(45): 28193-9).

- ⁽²⁾Hans et al. ("Regulation of keratin expression by retinoids", Dermatoendocrinol. 2011 Jul-Sep; 3(3): 136-140.).

Example 3: Anti-ageing comparative study of essential oil of lemon savory on keratinocytes and fibroblasts obtained in Example 1.

A. Principle

The aim of this study is to evaluate and compare the effects of the essential oil of lemon savory, the essential oil of winter savory and geraniol on the expression of epidermal and dermal markers modulated in the course of ageing. The markers were studied by transcriptome analysis by RT-qPCR. Retinoic acid is used as reference molecule (0.1 mM).

The essential oils are evaluated at 0.003% and geraniol, which constitutes 74% of the EssOs, is itself evaluated at 0.002%.

The various markers studied on frozen slices are:

- epidermal markers: HBEGF, KRT19

- dermal marker/DEJ: COL4A1.

B. Materials & Methods:

The human epidermal keratinocytes (NHK) or the human dermal fibroblasts (NHF) are seeded in 48-well culture plates and then cultured in adequate medium for three days at 37°C and 5% C02. At the end of the incubation, the culture medium is replaced with medium not containing (control) or containing the test compounds or the reference compound (retinoic acid at 0.1 mM for the NHKs or TGF-b at 10 ng/mL for the NHFs) and the cells are then incubated for 24 hours. At the end of the treatments, the culture media are removed, the cells are rinsed with PBS and the total RNAs are then isolated using a magnetic bead extraction kit and according to the supplier's recommendations. After analysis of the quality of the RNAs extracted and determination of their concentration, reverse transcription is performed to synthesize the cDNAs. The expression of the transcripts selected is then analysed by quantitative PCR using a LightCycler® 480 Real- Time PCR System in a 384-well plate (Roche) and according to the SYBR®Green (Qiagen) incorporation technique.

C. Results

The transcriptome data obtained on keratinocytes and fibroblasts show that the essential oil of lemon savory improves the skin quality when compared with geraniol alone, which, nevertheless, constitutes about 74% of the essential oil tested, and when compared with the EssO of winter savory.

The epidermal renewal markers (HBEGF" ( KRT 19^{a >}) are markedly increased after treatment with the EssO of lemon savory, whereas they are increased little or not at all with geraniol and the EssO of winter savory. The results for the EssO of lemon savory are of the same order as those observed with retinoic acid, which is known to be a powerful activator of epidermal renewal. The expression of collagen IV, which plays an important role for the firmness of the skin, is increased with the savory EssOs, whereas, once again, no effect is observed with geraniol, which is the major component (74%) of these essential oils.

Table 2: study by transcriptome analysis on keratinocytes

The data presented are modulation factors relative to the control. The data above 1.5 indicate stimulation of expression of the marker, whereas, on the other hand, the data below 0.5 indicate inhibition.

Table 3: study by transcriptome analysis on fibroblasts

- ^(l)Shirakata et al. ("Heparin-binding EGF-like growth factor accelerates keratinocyte migration and skin wound healing", Journal of Cell Science 2005 118: 2363- 2370)

- ⁽²⁾Brysk et al. ("Gene expression of markers associated with proliferation and differentiation in human keratinocytes cultured from epidermis and from buccal mucosa", Arch. Oral Biol. 1995 Sep; 40(9): 855-62). - ⁽³⁾Gillbro et al. ("in vivo topical application of acetyl aspartic acid increases fibrillin- 1 and collagen IV deposition leading to a significant improvement of skin firmness", Int. J. Cosmet. Sci. 2015 Oct; 37 Suppl 1 : 41-6.)

Example 3: Facial cream comprising an essential oil of lemon savory

Claims

1. Cosmetic use of at least one essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora, or of a cosmetic composition comprising said essential oil, as an active agent for improving the biomechanical properties of the skin.

2. Cosmetic use according to claim 1, in which the essential oil is an essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora, comprising more than 60% by weight of geraniol and more than 5% by weight of trans-P-carophyllene.

3. Cosmetic use according to claim 1 or claim 2, characterized in that said essential oil is obtained via a steam distillation process.

4. Cosmetic use according to any one of the preceding claims, characterized in that said cosmetic composition comprises between 0.001% and 5% by weight of an essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora.

5. Cosmetic use according to any one of the preceding claims, characterized in that the essential oil, or the composition comprising said essential oil, comprises geraniol, ΐ-b-caryophyllene, nerol, germacrene D, b-bisabolene and geranial.

6. Cosmetic use according to any one of the preceding claims, characterized in that said cosmetic composition comprising said essential oil comprises at least one other essential oil and/or hydro late.

7. Cosmetic use according to any one of the preceding claims, characterized in that said essential oil or said composition is used for improving the firmness of the skin.

8. Cosmetic use according to any one of the preceding claims, characterized in that said essential oil or said composition is used for treating or preventing the cosmetic signs associated with ageing of the skin, in particular related to age or to exposure to sunlight.

9. Cosmetic use according to any one of the preceding claims, characterized in that said essential oil or said composition is suitable for topical administration.

10. Cosmetic process for improving the biomechanical properties of the skin, comprising a step consisting in applying at least one essential oil of lemon savory, in particular Satureja Montana L. ssp. citriodora, or a cosmetic composition comprising said essential oil, as an active agent.