Cosmetic treatment process capable of preserving the pH of keratin materials

Abstract

Cosmetic treatment process capable of preserving the pH of keratin materials The present application relates to a cosmetic treatment process for keratin materials comprising the following steps. a) At least one application of at least one cosmetic composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, followed by b) At least one application of at least one cleansing cosmetic composition B, to preserve and / or strengthen the barrier function of the skin and / or its appendages, to maintain the integrity of the stratum corneum, to defend and maintain the microbiota beneficial to keratin materials and / or to preserve the acid pH of the skin and / or its appendages.

Description

Title of the invention: Cosmetic treatment process capable of preserving the pH of keratin materials

[0001] The present invention relates to the field of skin care and / or its appendages, and relates in particular to a cosmetic procedure capable of preserving the pH of keratin materials, and preferably of the skin and / or its appendages, when a cleansing cosmetic and / or dermatological composition is applied to the latter.

[0002] The subject of the invention is a process for the cosmetic and / or dermatological treatment of keratin materials comprising the following steps:

[0003] a) At least one application of at least one cosmetic and / or dermatological composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, followed by

[0004] b) At least one application of at least one cosmetic and / or dermatological cleansing composition B.

[0005] It thus finds use in the preservation of homeostasis of the barrier function, the maintenance of the integrity of the stratum corneum, antimicrobial defense and the maintenance of a microbiota beneficial to keratin materials and more preferentially to the skin.

[0006] The skin is the body's first barrier to the external environment. Human skin is made up of several compartments, three of which cover the entire body, namely a superficial compartment, the epidermis, the dermis, and a deep compartment, the hypodermis.

[0007] The dermis provides the epidermis with a solid support. It is also its nourishing element. It is mainly made up of fibroblasts and an extracellular matrix composed mainly of collagen, elastin and a substance called ground substance, components synthesized by the fibroblast. It also contains dendritic cells, mast cells and tissue macrophages. It also contains blood vessels and nerve fibers.

[0008] The epidermis is in contact with the external environment. The natural human epidermis is composed mainly of three types of cells which are keratinocytes, which are the vast majority, melanocytes and Langerhans cells. The cells constituting the epidermis are delimited by an intercellular lipid domain. Each of these cell types contributes through its own functions to the essential role played in the body by the skin. In particular, keratinocytes undergo a continuous and oriented maturation process which, keratinocytes located in the layer basal layer of the epidermis, results in the formation of corneocytes, which are dead, fully keratinized cells made up of keratinocytes in the terminal stage of their differentiation. During differentiation, the phospholipids whose role is to develop the fluid structure of the cell membranes of the living layers of the epidermis, are gradually replaced by a mixture composed mainly of fatty acids, cholesterol and sphingolipids (ceramides). These lipids, which are organized in specific lamellar liquid crystal phases, form the intracellular cement of the stratum corneum and are essential for water exchange and the barrier function of the epidermis. Thus, the lamellar structure of the lipids of the lipid domain of the epidermis and the corneocytes participate in the epidermal barrier function.The skin thus constitutes a barrier against external aggressions, in particular chemical, mechanical or infectious, and as such a certain number of defense reactions against environmental factors (climate, ultraviolet rays, tobacco, etc.) and / or xenobiotics, such as micro-organisms, occur at its level.

[0009] This property, called "barrier function", is mainly ensured by the most superficial layer of the epidermis, namely the horny layer, called the stratum corneum. The horny layer constitutes a real protective barrier against exogenous factors and endogenous water loss. Its good renewal as well as the quality of its structure are essential to ensure an effective barrier against the outside world and limit water loss which causes dehydration and dry skin.

[0010] It is now known that when the pH of the skin is inappropriate or changes to neutral or alkaline, as a result of frequent cleansing or illness, lipase activity decreases, as does the synthesis of ceramides, cholesterols and fatty acids, which form intercellular lipids, thus damaging the barrier function (Effects of soaps and detergents on skin surface pH, stratum corneum hydration and fat content in infants. Dermatology 1997; 195: 258-262). In addition, it has been shown that a neutral or weakly alkaline pH can lead to the formation of conditions that favor the proliferation of certain microorganisms in the skin, destabilizing the skin microbiota, thus causing various skin diseases (The effect of detergents on skin pH and its consequences. Clin Dermatol. 1996; 14(1): 23-27.).Finally, it is known that an increase in skin pH can lead to a weakening of the barrier function, and can then result in the appearance of sensitive skin, dry skin and even atopic skin (Abnormal skin barrier in the pathogenesis of atopic dermatitis. Peter M. Elias, MD University of California, San Francisco, CA 94121).

[0011] People more particularly affected by these alterations in the barrier function may be the following: people with so-called “fragile” or “delicate” skin » and vulnerable (case of baby skin for example); people with so-called “fragile” skin, including in particular people whose protective hydrolipidic film composed of sweat, sebum and natural moisturizing factors becomes scarce, as is the case for people aged over 60 and particularly in the context of old age (at least 75 years); people whose composition of the hydrolipidic film is modified, as is the case for people with diabetes, or dialysis, or suffering from certain diseases; people who have a lowered reactivity threshold due to neurogenic hyperactivity; these skins will therefore present these sensations and clinical signs much more quickly and frequently than other types of skin: these are people with sensitive skin.An alteration of the skin barrier function can notably result in a hydration disorder, a loss of skin suppleness, an alteration in the radiance of the complexion and the appearance of roughness on the skin.

[0012] Many environmental and cosmetic impurities are not water-soluble, and simply washing the skin with water is not sufficient to remove them. Substances capable of emulsifying them into finer particles are required to make these fat-soluble impurities water-soluble. Cosmetic cleansing compositions are surface-active substances (i.e., emulsifiers, detergents, surfactants, soaps) that decrease the surface tension on the skin and remove dirt, sebum, oils from cosmetic products, pathogenic microorganisms, and exfoliate comeal cells in emulsified form.

[0013] Cosmetic cleansing compositions are used to remove oils, impurities, contaminants (soil, dirt), and pathogenic bacteria from the skin. The presence of surfactants in these cleansing compositions significantly helps to separate impurities from the skin and to solubilize oily soils. Furthermore, in addition to allowing the removal of unwanted materials from the skin, the cleansing compositions help to promote normal exfoliation and therefore skin renewal.

[0014] However, regular use of cleaning compositions, and more particularly harsh cleansers, can lead to the appearance of dry skin, damage to the barrier function, erythema or itching. Surfactants represent the main constituents of cleaning compositions, and are mainly responsible for the cleaning action. They act by reducing inter-surface tension. They can be ionic, non-ionic, and contain silicones. Ionic surfactants can be anionic (negatively charged), cationic (positively charged) and amphoteric (positively charged) in nature. and negatively). The type and amount of surfactant in a cleaning composition influences its ability to dry and irritate the skin.

[0015] Treating the skin with aggressive cleansers leads to hyperhydration immediately after washing, followed by rapid evaporation of the water. Furthermore, the most aggressive cleansing compositions, such as those comprising soap-based surfactants, tend to interact with skin proteins and lipids, particularly those in the stratum corneum, leading to damage to the barrier function and are therefore likely to cause dry skin, skin irritation, redness, discomfort (such as tightness, heat, itching). These interactions can indeed negatively affect skin hydration and viscoelasticity.

[0016] The extent of damage to the skin depends on the nature of the surfactants, and the cleansing conditions. These effects can also be aggravated by other factors such as age, heredity, nutrition, external conditions and pre-existing skin problems (dry skin, sensitive skin, eczema, dermatitis etc.). Even if the new generations of cosmetic cleansing compositions also include other active agents (such as emollients, moisturizers etc.) which can provide additional benefit, there remains a need to reduce the ability of cleansing compositions to damage the skin.

[0017] Minimizing the damage caused by cleaning compositions is an important step in achieving uncompromising cleaning. A balance must be found between cleansing the skin and preserving its homeostatic properties.

[0018] Among the avenues of research explored to resolve this problem are the development of modified anionic surfactants to reduce their capacity to damage / denature proteins, or the use of combinations of anionic surfactants with amphoteric or non-ionic surfactants. Other avenues are moving towards the exclusive use of gentle cleansing compositions, which are less aggressive for the skin but therefore have a reduced cleaning capacity.

[0019] There thus remains a need to thoroughly clean keratin materials, and preferably the skin and / or its appendages, while limiting their aggression and in particular avoiding altering their pH, which could have significant repercussions on the quality of the epidermis, for example. It has thus been discovered, surprisingly, that the application of at least one cosmetic and / or dermatological composition comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, prior to cleaning the keratin materials, makes it possible to resolve the drawbacks mentioned above. This discovery thus makes it possible to preserve and / or strengthen the barrier function of the skin and / or its appendages, to maintain the integrity of the stratum corneum, to defend and maintain the microbiota beneficial to keratin materials and / or to preserve the acid pH of the skin and / or its appendages. Technical field

[0020] Thus, according to a first of its aspects, the present invention relates to a method for the cosmetic and / or dermatological treatment of keratin materials comprising the following steps:

[0021] a) At least one application of at least one cosmetic and / or dermatological composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, followed by

[0022] b) At least one application of at least one cosmetic and / or dermatological cleansing composition B.

[0023] In the context of the present invention, and unless otherwise indicated, the following definitions apply:

[0024] By “skin and / or its appendages” is meant in particular the skin, mucous membranes, lips, scalp, eyelashes, eyebrows and hair.

[0025] By “effective quantity” we mean the quantity of an active ingredient which allows the desired effect to be manifested.

[0026] A composition A according to the invention is generally suitable for application to the skin or its appendages, in particular topical application to the skin, and therefore generally comprises a physiologically acceptable medium, i.e. compatible with the skin. It is preferably a cosmetically acceptable medium, i.e. which has a pleasant color, odor and feel and does not generate unacceptable discomfort, i.e. tingling, tightness, redness, likely to discourage the user from applying this composition.

[0027] The expression “at least one” is equivalent to “one or more”.

[0028] The expressions “between ... and ...”, “includes from ... to ...”, “formed from ... to ...”, and “ranging from ... to ...” must be understood inclusively, unless otherwise specified.

[0029] Other characteristics, variants and advantages of the compositions according to the invention will become more apparent on reading the description and examples which follow. Detailed description

[0030] As indicated previously, the present invention relates to a method for the cosmetic and / or dermatological treatment of keratin materials comprising the following steps.

[0031] a) At least one application of at least one cosmetic and / or dermatological composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, followed by

[0032] b) At least one application of at least one cosmetic and / or dermatological cleansing composition B.

[0033] Cosmetic and / or dermatological composition A

[0034] The method for cosmetic and / or dermatological treatment of keratin materials according to the present invention comprises a first step consisting of applying to the keratin materials to be treated at least one cosmetic and / or dermatological composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria.

[0035] Extracts of non-photosynthetic, non-fruiting filamentous bacteria

[0036] The bacterial extracts that can be used in composition A according to the invention are prepared from non-photosynthetic filamentous bacteria as defined according to the classification of Bergey's Manual of Systematic Bacteriology (vol. 3, sections 22 and 23, 9th edition, 1989), among which may be mentioned bacteria belonging to the order Beggiatoa, and more particularly bacteria belonging to the genera Beggiatoa, Vitreoscilla, Flexithrix or Leucothrix.

[0037] The bacteria which have just been defined and several of which have already been described generally have an aquatic habitat and can be found in particular in marine waters or in thermal waters. Among the bacteria which can be used, we can cite for example:

[0038] Vitreoscilla filiformis (ATCC 15551)

[0039] Vitreoscilla beggiatoids (ATCC 43181)

[0040] Beggiatoa alba (ATCC 33555)

[0041] Flexithrix dorotheae (ATCC 23163)

[0042] Leucothrix mucor (ATCC 25107)

[0043] Sphaerotilus natans (ATCC 13338).

[0044] Preferably, an extract of Vitreoscilla filiformis (ATCC 15551) will be used.

[0045] By "bacterial extract" according to the invention is meant an extract of bacterial biomass or any active fraction of said extract, in particular

[0046] (i) bacterial cells isolated from the culture medium, which have been concentrated, by example by centrifugation (“unstabilized cell extract”);

[0047] (ii) concentrated bacterial cells (i), then subjected to an operation of breaking the envelopes of the bacterial cells, by any means known to those skilled in the art, such as the action of ultrasound or preferably autoclaving (“cell extract stabilized"). By "envelopes" we mean the bacterial wall and possibly the underlying membranes

[0048] (iii) the supernatant obtained by filtration of the stabilized cell extract (ii),

[0049] or any active fraction of said extract.

[0050] The bacterial extract as defined above (i), (ii) or (iii) also comprises, where appropriate, isolated culture medium used for the fermentation of said bacterium, initially separated during the concentration defined in (i) above. Said isolated culture medium can thus be added before or after the operations carried out in (ii) and (iii) above.

[0051] This active fraction can be obtained by conventional fractionation methods, such as extraction in the presence of a solvent, selective precipitation or tangential ultrafiltration (UFT) for example.

[0052] These extracts or fractions can be preserved for example by freezing said extracts or said fractions and used after thawing.

[0053] In the remainder of the description, we will speak more simply of “cellular extract” of bacteria ((i) and (ii)), of “supernatant” of said extract (iii) or of “active fraction”.

[0054] The extract of non-photosynthetic, non-fruiting filamentous bacteria that can be used in composition A used according to the invention is preferably chosen from a cell extract, the supernatant of said cell extract or an active fraction of said cell extract.

[0055] Preferably, the extract of non-photosynthetic, non-fruiting filamentous bacteria is an extract of Vitreoscilla filiformis, even more preferably a cellular extract of Vitreoscilla filiformis.

[0056] To prepare the bacterial extract used in composition A according to the invention, said bacteria can be cultivated according to methods known to those skilled in the art, or reference can be made in particular to the description of patent application WO-A-94-02158. A cell extract is obtained from which the supernatant can be separated, for example, by filtration and centrifugation. The extract can be used in aqueous form or in lyophilized form. The protocol is described in more detail in Example 1 below. This bacterial extract can be refractionated and used pure or diluted to different concentrations.

[0057] Composition A according to the present invention may contain the extract of non-photosynthetic, non-fruiting filamentous bacteria in the form of a dispersion in a suitable vehicle such as, for example, water, organic solvents, fatty substances including oils, and mixtures thereof, in particular emulsions. The mass contents indicated below relate to said extract of bacteria in dispersed form, in particular in dispersed form in water.

[0058] An extract of non-photosynthetic, non-fruiting filamentous bacteria, in particular Vitreoscilla filiformis extract, which can be used in the context of the present invention, is in particular available under the name Mexoryl SAH, marketed by the company Chimex (Noveal). This extract is an extract dispersed in water.

[0059] A composition A according to the invention advantageously comprises a mass content of extract of non-photosynthetic, non-fruiting filamentous bacteria, in particular of extract of Vitreoscilla filiformis ranging from 0.02% to 5%, in particular from 0.05% to 4%, even more particularly from 0.08% to 3% by weight relative to the total weight of dry extract of said composition A, in particular from 0.1% to 1.5% by weight.

[0060] Composition A according to the invention may be presented in all the galenic forms conventionally used for topical application and in particular in the form of an aqueous, alcoholic or hydroalcoholic solution or suspension or an oily solution or a solution or dispersion of the lotion or serum type, an emulsion of liquid or semi-liquid consistency of the milk type, obtained by dispersion of a fatty phase in an aqueous phase (O / W) or vice versa (W / O), or a suspension or emulsion of soft consistency of the cream type (O / W) or (W / O), multiple emulsions (triple: W / O / W or H / W / O), or an aqueous or anhydrous gel, a cream-gel, an ointment, or any other cosmetic form.

[0061] Preferably, a composition A according to the invention is in the form of a cream, a milk or a cream-gel.

[0062] According to a particular embodiment, a composition A according to the invention is in the form of a water-in-oil emulsion or cream.

[0063] According to another embodiment, a composition A according to the invention is in the form of a gel-cream

[0064] The quantities of the various constituents of a composition A used according to the invention are those conventionally used in the fields considered. A composition A according to the invention is prepared according to the usual methods. In addition, the composition A used according to the invention may be more or less fluid and have the appearance of a white or colored cream, an ointment, a milk, a lotion, a serum, a paste, a mousse. It may optionally be applied to the skin in the form of an aerosol. It may also be in solid form, for example in the form of a stick.

[0065] By “acceptable physiological environment” is meant a compatible environment with the skin and / or its appendages or the keratin materials and / or fibers of human beings, such as, for example, but not limited to, the skin, mucous membranes, nails, scalp and / or hair. Such a medium does not generate any tingling, tightness or redness unacceptable to the user. This physiologically acceptable medium comprises water, possibly mixed or not with one or more organic solvents such as CrC8 alcohols, including ethanol, isopropanol, tert-butanol, n-butanol, polyols such as glycerin, propylene glycol, butylene glycol and polyol ethers.

[0066] When the composition A used according to the invention, whatever its nature, comprises an oily phase, the latter preferably contains at least one oil. It may also contain other fatty substances. These fatty substances may be chosen in a varied manner by a person skilled in the art in order to prepare a composition A having the desired properties, for example consistency or texture.

[0067] As oils which can be used in composition A of the invention, we can cite for example:

[0068] - hydrocarbon oils of animal or vegetable origin, esters and ethers of synthesis, in particular of fatty acids, polyol esters, linear or branched hydrocarbons, of mineral or synthetic origin, fatty alcohols having 8 to 26 carbon atoms, partially hydrocarbon and / or silicone fluorinated oils, silicone oils, and their mixtures.

[0069] According to a particular embodiment of the invention, the composition A 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 A can range from 5 to 80% by weight, and preferably from 5 to 50% by weight relative to the total weight of the composition A. The emulsions according to the invention generally contain at least one emulsifier chosen from amphoteric, anionic, cationic or non-ionic emulsifiers, used alone or as a mixture, and optionally a co-emulsifier. The emulsifiers are chosen appropriately according to the emulsion to be obtained (W / O or O / W). The emulsifier and the co-emulsifier are generally present in composition A according to the invention, 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 composition A.

[0070] Mixture of non-ionic surfactants

[0071] In a preferred embodiment, composition A according to the invention is an H / W emulsion which comprises a mixture of non-ionic surfactants comprising (i) at least one ester of polyol and fatty acid and (ii) at least one ester of polyalkylene glycol and fatty acid and mixtures thereof.

[0072] i) Esters of polyalkylene glycol and fatty acids

[0073] The polyalkylene glycol and fatty acid esters suitable for composition A according to the invention are preferably chosen from esters of polyalkylene glycol and a C8-C24 fatty acid, in particular C10-C22, more particularly C12-C20, and more preferably C14-C18. Advantageously, the fatty acid and polyalkylene glycol esters will be chosen from esters of polyalkylene glycol and a C12-C22 fatty acid.

[0074] The fatty acid can be linear or branched, saturated or unsaturated.

[0075] As examples of polyalkylene glycol esters and fatty acids suitable for composition A according to the invention, mention may be made of polyalkylene glycol esters and of a fatty acid chosen from capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, arachidic acid, behenic acid, palmitoleic acid, oleic acid, linoleic acid, archidonic acid, or erucic acid. As an example of a C16-C20 fatty acid polymer, mention may be made of polyl2-hydroxystearic acid.

[0076] Preferably, a fatty acid may be chosen from lauric acid, stearic acid, behenic acid, arachadic acid or palmitic acid, and mixtures thereof.

[0077] The polyalkylene glycol sequences suitable for composition A according to the invention may advantageously be polyethylene glycol or polypropylene glycol sequences, or combinations thereof, and preferably are polyethylene glycol sequences, comprising from 1 to 100 units, in particular from 2 to 50 units, preferably from 4 to 40 units, more preferably from 6 to 30 units, and more preferably from 8 to 20 alkylene oxide units.

[0078] According to a preferred embodiment, the polyalkylene glycol and fatty acid esters which can be used in composition A according to the invention are esters formed from 1 to 100, or even from 2 to 75, or even from 3 to 50, and preferably from 4 to 40 ethylene oxide units and from at least one fatty acid chain comprising from 12 to 22 carbon atoms.

[0079] As an example of ethoxylated fatty esters which are particularly suitable for composition A according to the invention, mention may be made of the stearic acid ester comprising 40 ethylene oxide units, such as the product marketed under the name Myrj 52 ® (CTFA name: PEG-40 stearate) by the company ICI, or the behenic acid ester comprising 8 ethylene oxide units (CTFA name: PEG-8 behenate), such as the product marketed under the name Compritol HD5 ATO® by the company Gattefosse, or PEG-8 isostearate such as the product marketed under the name Prisorine 3644® by the company Uniquema, and mixtures thereof.

[0080] ii) Polyol and fatty acid ester

[0081] By "ester of polyol and fatty acid" according to the invention, is meant an ester of polyol and fatty acid or fatty acid polymer in which the fatty acid or the fatty acid polymer comprises at least one carboxylic function and a C7-C23 alkyl chain, and the polyol is chosen from glycerol, a polyglycerol, sorbitan, and mixtures thereof.

[0082] A polyol and fatty acid ester may be a polyester, and preferably be a diester of fatty acids and polyol.

[0083] A polyol and fatty acid ester suitable for composition A according to the invention may preferably be chosen from esters of polyol and a fatty acid or a polymer of fatty acid, and preferably a fatty acid, in C8-C24, in particular in C10-C22, more particularly in C12-C20, and more preferably in C14-C18.

[0084] The fatty acid can be linear or branched, saturated or unsaturated.

[0085] According to one embodiment, the fatty acid may be a dicarboxylic acid having 10 to 16 carbon atoms, such as sebacic acid or dodecanedioic acid.

[0086] As examples of polyol esters and fatty acids suitable for composition A according to the invention, mention may be made of polyol esters and of the fatty acid chosen from capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, arachidic acid, behenic acid, plamitoleic acid, oleic acid, linoleic acid, archidonic acid, or erucic acid. Preferably, the fatty acid is stearic or isostearic acid.

[0087] As an example of a C16-C20 fatty acid polymer, poly(l2-hydroxystearic acid) may be mentioned.

[0088] According to a particular embodiment, an ester of polyol and fatty acid is chosen from esters of glycerol or polyglycerol, and of C8-C24 fatty acid, and preferably C16-C20,

[0089] By polyglycerol is meant a compound of the following general formula:

[0090] [Chem.l]

[0091] in which the degree of condensation n ranges from 1 to 11, preferably from 2 to 9 and even more preferably from 3 to 5.

[0092] As preferred polyglycerol and fatty acid esters for composition A according to the invention, mention may in particular be made of: polyglycerol isostearate (4 moles) (INCI name: Polyglyceryl-4 Isostearate) sold under the name Isolan GI34® by Goldschmidt, polyglyceryl-4 diisostearate polyhydroxystearate sebacate sold under the name Isolan GPS® by Goldschmidt, the mixture of sorbitan isostearate and polyglycerol isostearate (3 moles) marketed under the name Arlacel 1690® by the company Uniqema, and mixtures thereof.

[0093] As examples of polyol and fatty acid esters that can be used in the composition of the invention, mention may be made of polyol and isostearic acid esters and their mixtures, in particular esters of isostearic acid and glycerol and / or sorbitan, such as, for example, polyglycerol isostearate (4 moles) (INCI name: Polyglyceryl-4 Isostearate) sold under the name Isolan GI34® by the company Goldschmidt, polyglycerol diisostearate (3 moles) sold under the name Lameform TGI® by Cognis; polyglycerol distearate (2 moles) sold under the name Emalex PGSA® by Nihon Emulsion; polyglycerol monoisostearate (10 moles) sold under the name Nikkol decaglyn 1 -IS® by Nihon Surfactant (INCI name: Polyglyceryl-10 isostearate); polyglyceryl-4 diisostearate polyhydroxy stearate sebacate sold under the name ISOLAN GPS® by Goldschmidt; the mixture of sorbitan isostearate and glycerol isostearate, such as the product marketed under the name Arlacel 986 by ICI, the mixture of sorbitan isostearate and polyglycerol isostearate (3 moles) marketed under the name Arlacel 1690® by UniQema, and mixtures thereof.

[0094] Preferably, as polyol and fatty acid ester suitable for composition A according to the invention, mention may be made of glyceryl monoisostearate, such as the product sold under the name Peceol Isostarique® by the company Gattefosse, polyglycerolated isostearate (4 moles) sold under the name Isolan GI34® by the company Goldschmidt, polyglycerolated diisostearate (3 moles) sold under the name Lameform TGI by the company Cognis and polyglycerolated distearate (2 moles) sold under the name Emalex PGSA by the company Nihon Emulsion.

[0095] Preferably, the non-ionic surfactant of the polyol and fatty acid ester type is present in an active material content varying from 0.1 to 10% by weight, preferably from 0.2 to 8% by weight, better still from 0.3 to 6% by weight and even better still from 0.4 to 3% by weight relative to the total weight of composition A.

[0096] Preferably, the non-ionic surfactant of polyalkylene glycol and fatty acid ester type is present in an active material content varying from 0.1 to 10% by weight, preferably from 0.2 to 8% by weight, better still from 0.3 to 8% by weight and even better still from 0.4 to 3% by weight relative to the total weight of composition A.

[0097] Preferably, the mixture of non-ionic surfactants is present in an active material content varying from 0.2 to 10% by weight, preferably from 0.4 to 8% by weight, better still from 0.6 to 6% by weight and even better still from 0.8 to 4% by weight relative to the total weight of composition A.

[0098] More particularly, the mixture of glyceryl monostearate and PEG 100 stearate (INCI name: GLYCERYL STEARATE (and) PEG-100 STEARATE) such as the product sold under the trade name Arlacel 165 sold under the name Arlacel 165® by the company Croda will be used.

[0099] In a known manner, the cosmetic or dermatological composition A according to the invention may also contain adjuvants usual in the cosmetic or dermatological field, such as hydrophilic or lipophilic gelling agents, preservatives, solvents, perfumes, fillers, UV filters, bactericides, absorbers odor, coloring matters, plant extracts, salts, antioxidants, basic agents, acids, non-ionic, anionic, cationic surfactants.

[0100] The quantities of these different adjuvants are those conventionally used in the field considered, and for example from 0.01 to 20% of the total weight of composition A. These adjuvants, depending on their nature, can be introduced into the fatty phase, into the aqueous phase and / or into the lipid vesicles.

[0101] Additional assets

[0102] Composition A according to the invention may also contain other active agents, and in particular at least one compound chosen from: moisturizing agents; depigmenting agents; anti-aging / anti-wrinkle agents; agents having a restructuring effect on the skin barrier function; agents promoting the maturation of the horny envelope; agents promoting skin microcirculation; agents stimulating the cellular energy metabolism of cells; tightening agents; antioxidant agents; anti-pollution and / or anti-free radical agents, desquamating agents, sunscreens, and mixtures thereof.

[0103] In the context of the present invention, the cosmetic and / or dermatological composition A is applied to keratin materials and more preferably to the skin and / or its appendages.

[0104] Mode of application

[0105] In a particular embodiment of the present invention, the cosmetic and / or dermatological composition A is applied to the keratin materials, and preferably to the skin and / or its appendages, at least once a day, and preferably more than once a day. In a particular embodiment, the composition A according to the invention is applied to the keratin materials, preferably to the skin and / or its appendages, from 1 to 10 times a day, preferably from 2 to 6 times a day, preferably from 3 to 5 times a day.

[0106] In one embodiment of the invention, the composition A according to the invention is applied to the keratin materials, and preferably to the skin and / or its appendages, for a period of at least one day, preferably at least 2 days, at least 5 days, at least 10 days, at least 20 days, and / or at least 30 days before the application of the cleansing composition B. In a particular embodiment, the composition A according to the invention is applied to the keratin materials, and preferably to the skin and / or its appendages, for a period of 1 to 30 days, preferably 5 to 20 days, preferably 10 to 15 days before the application of the cleansing composition B.

[0107] In a particular embodiment, the composition A according to the invention is applied to keratin materials, and preferably the skin and / or its appendages, with an interval of at least one day, preferably at least 2 days, between 2 successive applications.

[0108] In one embodiment of the invention, the composition A according to the invention is applied to the keratin materials, and preferably to the skin and / or its appendages, and is left in contact with the keratin materials, and preferably the skin and / or its appendages, for a period of at least 1 hour, preferably at least 3 hours, at least 6 hours, at least 12 hours, and / or at least 24 hours. In a particular embodiment, the composition A according to the invention is applied and left on the keratin materials, and preferably the skin and / or its appendages, for a period of 1 to 24 hours, preferably 10 to 20 hours.

[0109] In a particular embodiment, the application of composition A according to the invention is preferably carried out on dry, clean, washed and rinsed skin. In a preferred embodiment, the skin is washed, rinsed and optionally dried every day before application of composition A according to the invention with a mild cleanser.

[0110] Cosmetic and / or dermatological cleansing composition B

[0111] The method for cosmetic and / or dermatological treatment of keratin materials according to the present invention comprises a second step consisting of applying to the keratin materials to be treated at least one cosmetic and / or dermatological cleansing composition B.

[0112] A cosmetic and / or dermatological cleansing composition B as implemented in the context of the present invention comprises at least one active substance on the surfaces of keratin materials, preferably the skin and the mucous membranes, such as an emulsifier, a detergent, a surfactant, a soap, capable of reducing the surface tension of impurities, chemical molecules or microorganisms present on the keratin materials. Such active substances make it possible in particular to remove dirt, sebum, oils from cosmetic products, microorganisms from treated keratin materials, and more particularly from the skin and / or its appendages, and advantageously contribute to the exfoliation of the cells of the stratum corneum in emulsified form.

[0113] In a particular embodiment of the invention, the cleaning composition B comprises ionic, non-ionic, or silicone-containing surfactants. The ionic surfactants may be anionic (negatively charged), cationic (positively charged) and / or amphoteric (positively and negatively charged) in nature.

[0114] A cosmetic and / or dermatological cleansing composition B as implemented within the framework of the present invention advantageously corresponds to one of the following 3 forms: it can be chosen from cosmetic and / or dermatological compositions dermatological cleansing compositions based on soap or soap derivatives, cosmetic and / or dermatological cleansing compositions based on synthetic detergents and cosmetic and / or dermatological cleansing compositions of the “mixed” type.

[0115] Cosmetic and / or dermatological cleansing compositions based on soap or soap derivatives are composed of alkali salts of long-chain fatty acids and generally have a pH ranging from 9 to 10. Among them, soap-based compositions generally comprise the combination of long-chain fatty acids (tallow, palm oil, palm stearin, etc.) and oils comprising shorter carbon chains (palm kernel oil, coconut oil, etc.). They may also comprise water, glycerin, salts, perfume and other additives to improve the aesthetic appearance and performance of the composition.Derivatives of such compositions include clear compositions, containing glycerin as a humectant to counter the drying effects of soap; superfatted soap compositions, containing higher amounts of lipids, such as triglycerides, lanolin, paraffin, stearic acid or mineral oils to generate a protective film on the skin and deodorant / antibacterial soap compositions, which contain antimicrobial agents such as trichlosan, trichlocarban or carbanil to inhibit the growth of bacteria and therefore the presence of odor.

[0116] Cosmetic and / or dermatological cleansing compositions based on synthetic detergents (or "Syndet", for "synthetic detergent") comprise synthetic surfactants not generated by saponification, such as fatty acid isethionates or sulfosuccinic acid esters or mixtures thereof as the main ingredient and comprise little or no soap. Compositions based on synthetic detergents have a neutral or slightly acidic pH, are less irritating to the skin and do not form a layer of soap foam. Compared to cleansing compositions based on soaps or derivatives, those based on Synthetic detergent compositions may further advantageously comprise high concentrations of emollients and conditioners, and fillers or masking agents. They generally have better rinsing properties than compositions based on soaps or derivatives.

[0117] Mixed-type cosmetic and / or dermatological cleansing compositions consist of an alkaline soap to which surfactants with a pH of 9 to 10 have been added. These compositions provide gentler cleansing of keratin materials than that resulting from the use of compositions based on soaps or derivatives and also have superior cleansing properties to compositions based on synthetic detergents. Mixed-type cleansing compositions are also more foaming than compositions based on synthetic detergents and rinse more easily in the presence of water containing calcium or magnesium salts (such as hard water for example).

[0118] In a preferred embodiment, the cosmetic and / or dermatological cleansing composition B as implemented in the context of the present invention is a hard cleansing composition (or hard cleanser), which is characterized by the fact that it comprises at least one soap or soap derivative, that it comprises at least one hard surfactant such as a sulfate-based surfactant, including in particular alkyl sulfates and alkyl ether sulfates, and / or that it has a pH greater than 6. A cleansing composition B according to the invention can thus be chosen from cosmetic and / or dermatological cleansing compositions based on soap or soap derivatives, or from cosmetic and / or dermatological cleansing compositions of mixed type, as described above.

[0119] In a particular embodiment, the keratin materials, and preferably the skin and / or its appendages, are rinsed and optionally dried after application of the cleansing composition B according to the invention. In a particular embodiment, the rinsing is carried out with water.

[0120] In a particular embodiment, the cleansing composition B is applied at least once, preferably at least twice to the keratin materials, and preferably to the skin and / or its appendages.

[0121] Composition

[0122] Compositions A and B intended to be implemented within the framework of the present invention are formulated for administration preferably by topical route.

[0123] The compositions according to the invention are preferably cosmetic compositions, namely cosmetically acceptable in order to be applied to keratin materials, in particular human materials, without altering them.

[0124] It is also clear that the effective quantity of active ingredients corresponds to the quantity necessary to obtain the desired result, and that the formulation of the compositions according to the invention depends on the use for which these compositions are intended. In particular, two main categories of topical compositions according to the invention can be distinguished, depending on the conditions under which they will be applied to the skin. The first category corresponds to cosmetic compositions, that is to say intended to be applied to healthy skin in order to improve its appearance and in particular its comfort. Healthy skin is defined by the absence of pathologies such as infections, inflammation, erythema, or injuries such as a burn or a cut. However, in this definition, healthy skin does not mean skin in perfect condition.In particular, healthy skin may show signs of dryness that may be of exogenous origin (the skin becomes dry, for example, when . from exposure to dry and very cold air), or of endogenous physiological origin (for example, at the time of the hormonal drop linked to menopause).

[0125] Advantageously, the cosmetic and / or dermatological treatment method according to the invention makes it possible to preserve and / or strengthen the barrier function of the skin and / or its appendages, to maintain the integrity of the stratum corneum, to defend and maintain the microbiota beneficial to keratin materials and / or to preserve the acid pH of the skin and / or its appendages.

[0126] The invention is illustrated in more detail by the examples presented below. Unless otherwise indicated, the quantities indicated are expressed as a mass percentage. Examples

[0127] Example 1: Preparation of an extract of Vitreoscilla filiformis

[0128] The Vitreoscilla filiformis strain (ATCC 15551) is cultured according to the method described in patent application WO-A-94-02158.

[0129] This is a continuous culture process. The culture is carried out at 26°C for at least 48 hours until a suitable cell concentration corresponding to an optical density at 600 nm greater than or equal to 1.5 is obtained. The strain is subcultured at 2% V / V in new medium for approximately 48 hours until a stable culture is obtained. A 1 liter Erlenmeyer flask containing 200 ml of new medium is then inoculated with 4 ml of the previous culture.

[0130] The Erlenmeyer flask culture is carried out at 26°C on a culture table shaken at 100 rpm. The resulting starter culture is used as an inoculum for a 50-litre fermenter. Growth takes place at 26°C, pH 7, 100 rpm and pO2>15%.

[0131] After 30 hours of growth, the biomass is transferred into a 3000 liter useful fermenter, to be cultivated under the same conditions. After 48 hours of growth, the cells are harvested continuously. The biomass is then concentrated approximately 50 times by centrifugation. The cells obtained are then frozen as the culture continues. These cells can be used as they are after thawing (unstabilized cell extract) or can be stabilized by autoclaving at 121°C for 20 to 40 minutes (stabilized cell extract). If necessary, these cells are resuspended in the culture medium to generate biomass before the autoclaving stabilization step.

[0132] The cells then burst during sterilization or autoclaving, releasing the cytosol and agglomerating the proteins and walls. The product obtained is then biphasic.

[0133] The supernatant liquid phase may be filtered at 0.22 pm to remove particles (“supernatant”).

[0134] The bacterial extract, in the form of cell extract (stabilized or not) or supernatant, can be used as is (aqueous form) or can be freeze-dried using conventional techniques (freeze-dried form).

[0135] Example!: skin test

[0136] Operating mode

[0137] In the tests carried out, the pH of the skin is measured before and after hard cleaning: the measurement is carried out on the left cheek of the volunteers with a COURAGE & KHAZAKA PH 900 PC Skin pH meter equipped with an Ingold® electrode. The quantity of H3O+ ions present on the surface of the skin is determined by measuring the potential difference between two electrodes combined into a single flat electrode:

[0138] - a Calomel reference electrode, and

[0139] - an electron-permeable glass electrode.

[0140] The planar configuration of this electrode allows maximum and uniform contact with the measured skin surface.

[0141] The tests were carried out on 46 male volunteers aged 18 to 50 (an average of 32 years), all with sensitive skin, with an equal distribution between the different skin types: oily skin (9 volunteers), oily combination skin (10 volunteers), normal (10 volunteers), dry skin (8 volunteers) and dry combination skin (9 volunteers).

[0142] The study was carried out as follows:

[0143] D-15: Volunteers cleaned their face once with water and without applying any cleansing product;

[0144] D-14: the volunteers cleaned their face with a strong cleanser corresponding to a commercial formula containing water, Triethanolamine, Myristic Acid, Lauric Acid, Glycerin, Lauryl Phosphate, Hydroxypropyl Methylcellulose, Cocamidopropyl Betaine, Phenoxyethanol, Perfume, Methylparaben, Butylated Hydroxy Toluene, Propylparaben, O-Cymen-5-ol (Isopropyl Methtylphenol), Ethylparaben, Benzophenone-4. The pH of their skin was measured before cleaning (T0), just after cleaning, then at 3h (T3) and 6h (T6) after cleaning according to the method described above;

[0145] From D-14 to D0: the volunteers cleaned their face once every day with a gentle cleanser, then applied a composition C (outside the invention) as described in table 1;

[0146] From D0 to D+1: the volunteers cleaned their face once with water and without applying any cleaning product;

[0147] D+l: Volunteers cleaned their face with a strong cleanser. Their skin pH was measured before cleaning (T0), just after cleaning, then 3h (T3) and 6h (T6) after cleaning according to the method described above;

[0148] From D+1 to D+14: the volunteers cleaned their face once every day with a gentle cleanser, then applied a composition A (according to the invention) as described in table 1;

[0149] From D+14 to D+15: the volunteers cleaned their face without applying any cleaning product;

[0150] D+15: Volunteers cleaned their face once with a strong cleanser. The pH of their skin was measured before cleaning (T0), just after cleaning, then 3 hours (T3) and 6 hours (T6) after cleaning according to the method described above.

[0151] The gentle cleanser composition used was as follows: Water, Glycerin, Pentaerythrityl Tetraethylhexanoate, Propylene Glycol, Ammonium Polyacryloyldimethyl Taurate, Polysorbate 60, Ceramide Np, Niacinamide, Sodium Chloride, Coco-Betaine, Disodium Edta, Caprylyl Glycol, Panthenol, T-Butyl Alcohol, Tocopherol.

[0152] Washing with the strong cleaner was carried out according to the following procedure:

[0153] - Subjects clean their hands with a non-antibacterial gel.

[0154] - they then moisten their entire face with warm water using their hands,

[0155] - subjects take an amount equivalent to a tablespoon of strong cleanser in one hand.

[0156] - they wash their face with their hands, making foam. They continue to do Lather all over face, including cheeks and neck, for 30 seconds.

[0157] - they then rinse the entire face, including the neck, with lukewarm water for at least 30 seconds.

[0158] - they then take a quantity corresponding to a tablespoon of cleaner strong in one hand.

[0159] - they wash their face with their hands making foam and continue to do so Lather, including cheeks and neck, for 30 seconds.

[0160] - the subjects then rinse their entire face, including the neck, with lukewarm water for at least minus 30 seconds.

[0161] - they finally dry the face very delicately with a soft, sterile cloth or a new pack of clean, disposable paper towels (new pack every day).

[0162] [Tables 1] INCI Name Composition A (according to the invention) Composition C (excluding the invention) GLYCERYL STEARATE (a nd) PEG-100 STEARATE 2.5 2.5 HYDROGENATED POLYI SOBUTENE 5 5 PEG-40 STEARATE 2.5 2.5 DIMETHICONE 10 10 CARBOMER 0.3 0.3 CETYL ALCOHOL 1 1 TRIETHANOL AMINE 0.3 0.3 PRESERVATIVES 0.8 0.8 STEARYL ALCOHOL 1 1 VITREOSCILLA FERMEN T 5 0 WATER Qsp 100 Qsp 100

[0163] [Tables2] T0 (before cleaning) T3 T6 ApH (±ET) 95% CI ApH (±ET) 95% CI ApH (±ET) 95% CI H vs J -1 -0.08 (±0 [-0.31;0 -0.68 (±0 [-0.82; -0 -0.44 (±0 [-0.61; -0 4 .12) .15] .07) .55] .08) .28] D15 vs D - -0.35 (±0 [-0.58; -0 -0.80 (±0 [-0.95; -0 -0.63 (±0 [-0.83; -0 14 .11) .12] .08) .65] .10) .44] D15 vs H -0.27 (±0 [-0.50; -0 -0.12 (±0 [-0.25; 0 -0.19(+0 [-0.36; -0 .12) .04] .07) .02] .08) .02]

[0164] The active ingredient used in the present example is an extract of Vitreoscilla filiformis. The latter is as described in the description above, and more precisely, that sold by the company Chimex (Noveal) under the name Mexoryl SAH.

[0165] The results of the experiments carried out presented in Table 2 above show that the use of the composition according to the invention for 14 days (D15) results in a significant drop in the pH of the skin, compared to day D-14 (bare skin) and day 1 (vehicle).

[0166] The strong cleanser in fact destabilizes the pH of the skin, and causes a strong increase in pH from 5.9 to 7. The prior use of a composition according to the invention for 14 days before cleaning the skin with a strong cleanser results in a significant drop in the pH of the skin at T6h, compared to non-cleansed skin. treated (J-14) or compared to skin treated with a composition outside the invention J1 (vehicle).

[0167] The composition according to the invention is significantly more effective than the vehicle, and allows a 5.72 faster recovery after an attack such as the use of a strong cleaner

Claims

Claims

1. Process for the cosmetic treatment of keratin materials comprising the following steps: a) at least one application of at least one cosmetic composition A comprising, in a physiologically acceptable medium, at least one extract of non-photosynthetic, non-fruiting filamentous bacteria, followed by b) at least one application of at least one hard cleansing cosmetic composition B, comprising at least one soap and / or soap derivative; at least one hard surfactant such as sulfates and / or derivatives, and / or which has a pH greater than 6.

2. Cosmetic treatment method according to claim 1, in which the extract of non-photosynthetic, non-fruiting filamentous bacteria is present in a mass content ranging from 0.02% to 5%, in particular from 0.05% to 4%, even more particularly from 0.08% to 3% by weight relative to the total weight of dry extract of composition A, in particular from 0.1 to 1.5% by weight.

3. Cosmetic treatment method according to any one of claims 1 to 2, in which the extract of non-photosynthetic non-fruiting filamentous bacteria is an extract of Vitreoscilla filif or even more preferably a cellular extract of Vitreoscilla filiformis.

4. Cosmetic treatment method according to any one of the preceding claims, in which composition A is applied to the keratin materials, at least once a day, and preferably more than once a day, from 1 to 10 times a day, preferably from 2 to 6 times a day, preferably from 3 to 5 times a day.

5. Cosmetic treatment method according to any one of the preceding claims, wherein composition A is applied to the keratin materials, preferably to the skin, for a period of at least one day, preferably at least 2 days, at least 5 days, at least 10 days, at least 20 days, and / or at least 30 days before the application of cleansing composition B, and / or for a period of 1 to 30 days, preferably 5 to 20 days, preferably 10 to 15 days before the application of cleansing composition B.

6. Cosmetic treatment process according to any one of the preceding claims, in which composition A is left in contact with the keratin materials after application, for a period of at least 1 hour, preferably at least 3 hours, at least 6 hours, at least 12 hours, and / or at least 24 hours, and / or for a period of 1 to 24 hours, preferably 10 to 20 hours.

7. Cosmetic treatment process according to any one of the preceding claims, in which the application of composition B to the keratin materials is followed by rinsing, preferably with water, and optionally by drying.

8. Cosmetic treatment method according to any one of the preceding claims, for preserving and / or strengthening the barrier function of the skin and / or its appendages, for maintaining the integrity of the stratum corneum, for defending and maintaining the microbiota beneficial to keratin materials and / or for preserving the acid pH of the skin and / or its appendages.