Use of a personal care composition

Abstract

The present invention relates to a personal care composition. Particularly, the present invention relates to a use of a combination of a sugar alcohol and a polyalkylene glycol, as a prebiotic in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for protecting skin against harmful microorganisms and for providing skin brightening.

Description

[0001] USE OF A PERSONAL CARE COMPOSITION

[0002] Field of Invention

[0003] The present invention relates to a personal care composition. Particularly, the present invention relates to a use of a personal care composition that protects skin against harmful microorganisms. The present invention also relates to a use of the personal care composition that provides melanin reduction I skin brightening.

[0004] Background to the Invention

[0005] Skin in mammals is considered as one of the largest organs in the body and has the largest surface area. Skin forms the first line of defence against microorganisms which may invade the body though the air, water, food or material that come in contact with the body. When the body is infected on the skin or systemically, a traditional approach to such hygiene problems has been to treat the skin / body with antimicrobial actives that reduce or kill the germs. Recent research indicates that a lot of the bacteria that permanently reside on the skin (called skin commensal bacteria) do not actually cause infections, rather they are beneficial bacteria that protect the skin against disease causing pathogens. Several mechanisms have been proposed to explain the protection and some of the popular ones are: physically occupying space on skin to prevent colonization of pathogens; producing metabolites that ward of possibly pathogenic organisms; generating metabolites that strengthen the innate defence mechanisms to prevent infection by harmful pathogens; and providing other benefits such as maintaining skin pH, barrier function etc.

[0006] Thus, of late, there is a trend in moving away from the approach of treating the skin with broad spectrum antimicrobial actives that tend to also kill such commensals present on the skin (or any other part of the body) as a means of treating infections.

[0007] The present inventors, whilst working in the field of skin treatments, have surprisingly found that a combination of a sugar alcohol and a polyalkylene glycol acts as a prebiotic, as in, it provides a prebiotic benefit. They further found that when such prebiotic combination was incorporated in a personal care composition that comprises one or more activators of peroxisome proliferator-activated receptors (PPAR activator), it provided an effective way to protect the skin against harmful microorganisms; and it also provided skin brightening. Summary of the Invention

[0008] Accordingly, in a first aspect, the present invention relates to use of a combination of: a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for protecting skin against harmful microorganisms.

[0009] In a second aspect, the present invention relates to a use of a combination of: a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for providing skin brightening.

[0010] Detailed Description of the Invention

[0011] All other aspects of the present invention will more readily become apparent from the description and examples which follow.

[0012] Any feature of one aspect of the present invention may be utilized in any other aspect of the invention. The word “comprising” is intended to mean “including” but not necessarily “consisting of” or “composed of.” In other words, the listed steps or options need not be exhaustive. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and / or use are to be understood as modified by the word “about”. Numerical ranges expressed in the format " x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "x to y", it is understood that all ranges combining the different endpoints are also contemplated. Unless specified otherwise, amounts as used herein are expressed in percentage by weight based on total weight of the composition and may be abbreviated as “wt%”. The use of any and all examples or exemplary language e.g. “such as” provided herein is intended merely to better illuminate the invention and does not in any way limit the scope of the invention otherwise claimed. Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and / or use may optionally be understood as modified by the word “about”.

[0013] Skin, as used herein, means the skin on the feet, face, neck, chest, arms (including underarms), hands, legs, buttocks, back and scalp (including hair). A personal care composition as per the present invention may be in the form of a leave-on composition (for example creams, lotions, serums, gels, balms, deodorants and antiperspirants including aerosols), or a wash-off form (for example, shampoos, conditioners, handwash, bodywash compositions). In one aspect, the end use composition of the present invention is a personal wash composition, a face wash product or a leave-on product, such as a cosmetic cream or lotion to be applied to the face, body or hands.

[0014] For the purposes of the present invention, the term ‘prebiotic’ preferably means, a substance or an ingredient that acts as a nutrient for, and promotes a healthy environment, for the commensal bacteria that are commonly present on the skin.

[0015] It has been found that the combination of a sugar alcohol and a polyalkylene glycol functions as a prebiotic and induces secretion of short chain fatty acids which are known to provide antimicrobial effect e.g. antibacterial effect. It has further been found that when the prebiotic combination was comprised in a personal care composition that also comprises one or more PPAR activators, protection of skin against harmful microorganisms is obtained.

[0016] Accordingly, in a first aspect, the present invention relates to use of a combination of: a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for protecting skin against harmful microorganisms.

[0017] Preferably, such harmful microorganisms are one or more of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Cutibacterium acnes (C. acnes).

[0018] Preferably, the use as described above is non-therapeutic or cosmetic in nature. It has also been found that when the prebiotic combination was comprised in a personal care composition that comprises one or more PPAR activators, skin brightening or reduction in melanin was obtained.

[0019] Accordingly, in a second aspect, the present invention relates to a use of a combination of: a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for providing skin brightening.

[0020] Preferably, the use as described above is non-therapeutic or cosmetic in nature.

[0021] Thus, a composition as per the present invention (the composition) comprises a sugar alcohol, a polyalkylene glycol and a one or more PPAR activators.

[0022] It has further been found that the prebiotic combination, when comprised in a personal care composition comprising one or more PPAR activators, provide anti-aging benefit and also improve the barrier function of skin.

[0023] The composition comprises a sugar alcohol. Preferably, the sugar alcohol is selected from glycerol, erythritol, xylitol, mannitol, sorbitol, galactitol, inositol, lactitol, and mixtures thereof. More preferably, the sugar alcohol is selected from glycerol, lactitol, sorbitol and mixtures thereof. More preferably, the sugar alcohol is selected from glycerol, lactitol and mixtures thereof. Most preferably, glycerol is selected as the sugar alcohol.

[0024] Preferably, the composition comprises one or more sugar alcohols as described above in an amount from 0.1 to 80 wt%, preferably from 0.5 to 50 wt%, preferably from 1 to 30 wt%, preferably from 3 to 20 wt%, preferably from 5 to 15 wt%, preferably from 7 to 12 wt%.

[0025] The composition comprises a polyalkylene glycol. Preferably, the average molecular weight of the polyalkylene glycol is at least 200 Daltons. Preferably, the average molecular weight of the polyalkylene glycol is at max 150000 Daltons, e.g. 108000 and 100000 Daltons. Preferably, the molecular weight of the polyalkylene glycol is in the rage from 200 to 150000 Daltons. Preferably, the polyalkylene glycol is selected from polyethylene glycol (PEG), polypropylene glycol (PPG), polybutylene glycol (PBG) and mixtures thereof. More preferably, the polyalkylene glycol selected is PEG.

[0026] Examples of polyalkylene glycols that are suitable to be used in the present invention include PEG 200 (average molecular weight 200 Daltons commercially available from SIGMA (catalogue: P3015), PEG 550 (average molecular weight 550 Daltons) commercially available from SIGMA (catalogue: 409510), PEG 8000 (average molecular weight 8000 Daltons) commercially available from SIGMA (catalogue: P2139), PEG 100000 (average molecular weight 100000 Daltons) commercially available from SIGMA (catalogue: 181986) and PEG 108000 (average molecular weight 108000 Daltons) commercially available from SIGMA (catalogue: 81201).

[0027] The polyalkylene glycol are polyalkylene glycols with average molecular weight such that they are water soluble.

[0028] Preferably, composition comprises one or more polyalkylene glycols in an amount from 0.1 to 20 wt%, more preferably from 1 to 18 wt%, even more preferably from 3 to 15 wt%, further more preferably form 5 to 12 wt% and still more preferably from 7 to 10 wt%.

[0029] Preferably, the composition comprises a sugar alcohol and a polyalkylene glycol in weight ratio in the range from 1 :20 to 20: 1 , preferably 1 : 15 to 15: 1 , preferably 1 : 10 to 10: 1 , preferably 1 :5 to 5:1 , preferably 1 :4 to 4:1 , preferably 1 :3 to 3:1 , preferably 1 :2 to 2:1 , preferably 1 :1.

[0030] For example, the composition may comprise a sugar alcohol (e.g. glycerol) and PEG (Average molecular weight 550 Daltons) in wight ratio 1 :2 or 2:1 as exemplified herein below.

[0031] If the composition comprises more than one sugar alcohol, it will be understood that sum of all the sugar alcohols that may be present, needs to be taken in to account for the purpose of the ratio and in the same manner, for the polyalkylene glycol.

[0032] It has been found that when the composition comprising a sugar alcohol and a polyalkylene glycol is applied on skin, it resulted in secretion of short chain fatty acids which mediate an antimicrobial action that protects the skin from harmful microorganisms. Examples of short chain fatty acid includes lactic acid, acetic acid, glycolic acid, butyric acid and succinic acid. Thus, the combination of a sugar alcohol and a polyalkylene glycol works as a prebiotic, and is utilized by commensal bacteria e.g. Staphylococcus epidermidis, that is commonly present on the skin; and it results in secretion of such short chain fatty acids. It is particularly found that when the weight ratio of the sugar alcohol to a polyalkylene glycol is in the range 1 :20 to 20:1 for example 1:2 to 2:1, secretion of such short chain fatty acids was found to be improved.

[0033] The composition further comprises one or more PPAR activators, i.e. the composition preferably comprises at least one PPAR activator.

[0034] A PPAR activator that is suitable for use include 10-hydroxystearic acid (10-HSA) 12- hydroxystearic acid (12-HSA), cis parinaric acid, trans-7-octadecenoic acid, cis 5,8,11,14,17 eicosapentanoic acid, cis-4,7, 10, 13, 16, 19 docosahexenoic acid, conjugated linoleic acid (c9,t11), columbinic acid, linolenelaidic acid, ricinolaidic acid, stearidonic acid, 2- hydroxystearic acid, alpha-linolenic acid, arachidonic acid, cis-11 ,14-eicosadienoic acid, conjugated linoleic (t10,c12), conjugated linoleic acid (t9,t11), conjugated linoleic acid (50:50 mix of c9, t11 and t10 c12), coriander acids, linolelaidic acid, monopetroselinic acid, petroselinic acid, ricinoleic acid, stearolic acid, thuja extract or trans vaccenic acid.

[0035] Even other PPAR activators suitable for use include cis-11 ,14, 17 eicosatrienoic acid, cis-5 eicosenoic acid, cis-8,11,14 eicosatrienoic acid, hexadecatrienoic acid, palmitoleic acid, petroselaidic acid, cis 13, 16 docosadienoic acid, cis vaccenic acid, cis-11 eicosenoic acid, cis-13, 16, 19 docosatrienoic acid, cis-13-octadecenoic acid, cis-15-octadecanoic acid, cis- 7,10,13,16 docosatetraenoic acid, elaidic acid, gamma-linolenic acid, geranic acid, geranyl geranoic acid, linoleic acid, oleic acid, petroselinyl alcohol, phytanic acid, pinolenic acid, trans- 13-octadecenoic acid or tridecyl salicylic acid (TDS).

[0036] Preferably, the PPAR activator selected is petroselinic acid, conjugated linoleic acid, 12- HSA, 10-HSA, ricinoleic acid or a mixture thereof. More preferably, the PPAR activator is selected from 10-HSA, 12-HSA and mixtures thereof. Even more preferably, the PPAR activator that may be used in the composition is 12-HSA.

[0037] Preferably, the composition comprises one or more PPAR activators in an amount from 0.01 to 5 wt%, preferably from 0.1 to 4 wt% preferably from 1 to 3 wt%, preferably from 1.5 to 2 wt%. Preferably, the composition is a leave-on product. Examples of leave-on products include a cream, a lotion, a gel. More preferably, the composition is a leave-on product in the form of a cream. ‘Leave-on’ composition preferably means a composition which is not required to be removed from the surface it is applied on to, e.g. skin, after the application of the composition like e.g. skin cream, body lotion, hand sanitizer and deodorants.

[0038] If the composition is in the form of a cream, then it preferably further comprises from 3 to 25 wt%, more preferably 4 to 22 wt%, even more preferably from 7 to 20 wt%, further more preferably from 10 to 19 wt% and still more preferably 12 to 18 wt% fatty acids. Such fatty acids when present in the composition along with a soap, provide the so-called vanishing cream effect, i.e. a composition, when applied on to the human skin, vanishes on the skin leaving behind no significant streaks of the composition.

[0039] The fatty acids may be selected from fatty acids having carbon atoms preferably in the range 10 to 22, more preferably 12 to 22, even more preferably 14 to 22, further more preferably 16 to 22, yet more preferably from 18 to 22. Examples of such fatty acids that may be used in the composition include lauric, myristic, palmitic, stearic, isostearic, oleic, arachidic, behenic, erucic acid and mixtures thereof. Alternatively, the fatty acid that may preferably be used is stearic acid or palmitic acid or a mixture thereof. The fatty acid in the present invention is preferably hysteric acid which is substantially (generally about 90 to 95%) a mixture of stearic acid and palmitic acid where amount of palmitic acid may range from 40 to 65% and that of stearic acid may range from 34 to 58%.

[0040] If the composition is in the form of a cream, then it preferably further comprises from 0.1 to 10 wt%, more preferably 1 to 8 wt%, even more preferably 2 to 7 wt%, further more preferably 2 to 6 wt%, even further more preferably 2 to 5 wt% and most preferably 2 to 4 wt% soap.

[0041] Soap when present in the combination with the additional fatty acids in the composition, it provides the so-called vanishing effect. Soap of the invention is generally prepared by in-situ neutralization of the additional fatty acids that may be present in the composition. Thus, it is preferred that the soap has a carbon chain length that corresponds to the chain length of the additional fatty acids in the composition. The soap is formed from the additional fatty acids through the use of alkali metal hydroxides e.g. sodium hydroxide or potassium hydroxide. Of the two, potassium hydroxide is more preferred. Thus, the soap is preferably a potassium soap (potassium salt of fatty acid).

[0042] Preferably, the leave-on composition of the invention comprises water. Amounts of water may preferably range from 10 to 95 wt%, more preferably from 15 to 85 wt%, even more preferably from 35 to 80 wt%, and further more preferably from 40 to 75 wt%.

[0043] The leave-on composition of the invention may be in the form of an emulsion e.g. a water-in- oil emulsion or an oil-in-water emulsion, preferably an oil-in-water emulsion. In such cases, the composition may include mineral oils, silicone oils, and synthetic oils. Amounts of these materials may range from 0.1 to 50 wt%, and preferably, from 0.1 to 30 wt%, and most preferably, from 1 to 20 wt%, including all ranges subsumed therein.

[0044] Silicone oils may be divided into the volatile and non-volatile varieties. The term “volatile” as used herein refers to those materials which have a measurable vapor pressure at ambient temperature. Volatile silicone oils are preferably chosen from cyclic or linear polydimethylsiloxanes containing from 3 to 9, and preferably, from 4 to 5 silicon atoms.

[0045] Linear volatile silicone materials generally have viscosities of less than 5 centistokes at 25°C while cyclic materials typically have viscosities of less than 10 centistokes (measured with a Brookfield Viscometer, RV No. 3 spindle at 20 PRM, standardized to mineral oil and at 25°C).

[0046] Nonvolatile silicone oils useful as carrier material include polyalkyl siloxanes, polyalkylaryl siloxanes and polyether siloxane copolymers. The essentially non-volatile polyalkyl siloxanes useful herein include, for example, polydimethylsiloxanes (like dimethicone, including crosspolymers and elastomers) with viscosities of from 5 to 100,000 centistokes at 25°C.

[0047] An often-preferred silicone source is a cyclopentasiloxane and dimethiconol solution.

[0048] The leave-on composition of the invention may further comprise emollients. Examples of emollients that may be used in the composition include stearyl alcohol, glyceryl monoricinoleate, mink oil, cetyl alcohol, isopropyl isostearate, isobutyl palmitate, isocetyl stearate, oleyl alcohol, isopropyl laurate, hexyl laurate, decyl oleate, octadecan-2-ol, isocetyl alcohol, eicosanyl alcohol, behenyl alcohol, cetyl palmitate, silicone oils such as dimethylpolysiloxane, din-butyl sebacate, isopropyl myristate, isopropyl palmitate, isopropyl stearate, butyl stearate, polyethylene glycol, triethylene glycol, lanolin, cocoa butter, corn oil, cotton seed oil, olive oil, palm kernel oil, rape seed oil, safflower seed oil, evening primrose oil, soybean oil, sunflower seed oil, avocado oil, sesame seed oil, coconut oil, arachis oil, castor oil, acetylated lanolin alcohols, petroleum jelly, mineral oil, butyl myristate, isopropyl linoleate, lauryl lactate, myristyl lactate, decyl oleate, myristyl myristate and mixtures thereof. Such emollients may preferably be present in amounts 0.1 to 30 wt%, more preferably from 1 to 25 wt%, even more preferably from 3 to 20 wt%, further more preferably from 5 to 15 wt% and still more preferably from 7 to 12 wt%.

[0049] Emulsifiers (or surfactants) may be present in leave-on compositions comprising the components of the present invention. Total concentration of the emulsifier, when used, may range from 0.1 to 30 wt%, and preferably, from 2 to 20 wt%, and most preferably, from 1 to 9 wt% by weight of the composition. The emulsifier may be selected from the group consisting of anionic, nonionic, cationic and amphoteric components. Particularly preferred nonionic components are those with a C10 to C20 fatty alcohol or acid hydrophobe condensed with from 2 to 100 moles of ethylene oxide or propylene oxide per mole of hydrophobe; C2-C10 alkyl phenols condensed with from 2 to 20 moles of alkylene oxide; mono- and di-fatty acid esters of ethylene glycol; fatty acid monoglyceride; sorbitan, nono- and di- C8-C20 fatty acids; and polyoxyethylene sorbitan as well as combinations thereof. Alkyl polyglycosides and saccharide fatty amides (e.g. methyl gluconamides) are also suitable nonionic emulsifiers.

[0050] Preferred anionic emulsifiers include alkyl ether sulfate and sulfonates, alkyl sulfates and sulfonates, alkylbenzene sulfonates, alkyl and dialkyl sulfosuccinates, C8-C20 acyl isethionates, C8-C20 alkyl ether phosphates, alkylethercarboxylates and combinations thereof.

[0051] Cationic emulsifiers that may be used include, for example, palmitamidopropyltrimonium chloride, distearyldimonium chloride and mixtures thereof. Useful amphoteric emulsifiers include cocoamidopropyl betaine, C12-C20 trialkyl betaines, sodium lauroamphoacetate, and sodium laurodiamphoacetate or a mixture thereof.

[0052] Other generally preferred emulsifiers include glyceryl stearate, glycol stearate, stearamide

[0053] AMP, PEG-100 stearate, cetyl alcohol as well as emulsifying / thickening additives like hydroxyethylacrylate / sodium acryloyldimethyl taurates copolymer / squalene and mixtures thereof.

[0054] Alternatively, the composition may be in the form of a wash-off composition. Examples of such wash-off composition include a hand-wash composition, a body-wash composition and a shampoo composition.

[0055] By ‘wash-off’, it is preferably meant that the composition applied on to a surface e.g. skin, is removed from the surface preferably with water. In other words, the surface is rinsed-off with water and the composition so applied is removed. Typically, if the composition is formulated in the form of a wash-off composition, then the composition so applied is removed preferably within 5 minutes, more preferably within 3 minutes, even more preferably within 1 minute and further more preferably within 30 seconds e.g. 10 or 15 seconds, of it being applied on a surface.

[0056] If the composition is formulated in the form of a wash-off composition, e.g. a shampoo or wash composition, then the composition preferably comprises a surfactant. In such case, the composition preferably comprises surfactants in an amount from 3 to 80 wt%, preferably 5 to 80 wt% surfactant. Based on the whether the wash-off composition is formulated in a liquid format or a solid format, amounts and types of surfactants may vary.

[0057] For example, if the wash-off composition is formulated as a solid wash-off composition e.g. a bar, then the composition may comprise preferably from 25 to 70 wt%, preferably from 30 to 65 wt%, preferably from 35 to 60 wt%, preferably from 40 to 55 wt% surfactant e.g. a fatty acid soap and / or from 0.1 to 25 wt% preferably 1 to 22 wt%, preferably 3 to 20 wt%, preferably 5 to 15 wt% non-soap synthetic surfactant whereby the bars typically comprise 10 to 25 wt%, preferably 12 to 22 wt%, preferably 14 to 20 wt%, preferably 14 to 16 wt% water.

[0058] Alternatively, for example, if the wash-off composition is formulated as a liquid wash-off composition e.g. hand-wash or body-wash composition, then the composition preferably comprises from 3 to 20 wt%, preferably from 5 to 20 wt%, more preferably from 5 to 18 wt%, even more preferably from 5 to 15 wt%, further more preferably from 5 to 14 wt% and still more preferably from 5 to 12 wt% surfactant. Preferably, surfactants present in such wash-off compositions may be selected from an anionic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, a zwitterionic surfactant and mixtures thereof.

[0059] A suitable anionic surfactant may be selected from a soap and / or a non-soap synthetic anionic surfactant.

[0060] Examples of soap include soaps that may be used as anionic surfactants in a wash-off composition include those formed after saponification of fatty acids having carbon atoms in the range from C8to C20 with an aqueous alkali e.g. sodium hydroxide, potassium hydroxide and ammonium hydroxide. Typical examples of soap include caprylate (C8), caprates (C10), laurate (C12), myristate (C14), palmitate (C16, stearate (C18) and oleate (C18:1) formed with an aqueous alkali mentioned earlier. Thus, preferred soaps are selected from potassium caprylate, potassium caprate, potassium laurate, potassium myristate, potassium palmitate, potassium stearate, potassium oleate, sodium caprylate, sodium caprate, sodium laurate, sodium myristate, sodium palmitate sodium stearate, sodium oleate and mixtures thereof. Often, soaps may be present as a mixture of soaps formed from fatty acids of varying chain lengths.

[0061] Preferably, a non-soap synthetic anionic surfactants is selected from alkyl sulfates, alkyl ether sulfates (AES), alpha olefin sulfonates (AOS), isethionates, taurates and mixtures thereof.

[0062] Examples of alkyl sulfates that may be used as non-soap anionic surfactant in the composition include sodium lauryl sulfate (SLS), sodium myristyl sulfate, ammonium lauryl sulfate (ALS); sodium pareth sulfate, and mixtures thereof.

[0063] Examples of AES that may be used as non-soap anionic surfactants include anionic surfactants of the general formula:

[0064] R1-(OR’)n-O-SO3- M+, wherein:

[0065] R1 is saturated or unsaturated C8-C16, preferably C12-C14 alkyl chain; preferably, R1 is a saturated C8-C16, more preferably a saturated C12-C14 alkyl chain;

[0066] R’ is ethylene; n is from 1 to 18; preferably from 1 to 15, more preferably from 1 to 10 and even more preferably from 1 to 5, M+ is a suitable cation which provides charge neutrality, preferably sodium, calcium, potassium, or magnesium, ammonium, more preferably a sodium cation or ammonium.

[0067] Examples of AES that may be used as non-soap anionic surfactants in the composition include sodium lauryl ether sulfate (SLES), sodium myristyl ether sulfate and sodium palmityl ether sulfate, ammonium lauryl ether sulfate (ALES) and mixtures thereof. Preferred AES is SLES having 1 to 3 ethylene oxide units per molecule. SLES having 1 to 2 ethylene oxide units per molecule is more preferred.

[0068] Examples of AOS that may be used as non-soap anionic surfactant in the composition include sodium olefin sulfonate. Examples of isethionate that may be used as non-soap anionic surfactant in the composition include, sodium lauryl isethionate; sodium cocoyl isethionate. Examples of taurates that may be used as non-soap anionic surfactant in the composition include sodium taurates such as sodium lauryl methyl taurate and sodium cocoyl methyl taurate.

[0069] Preferably, nonionic surfactants are selected from: fatty alcohol ethoxylates with saturated carbon chain and having HLB higher than 15.5 e.g. Brij® 35 (also known as Brij® L23), fatty alcohol ethoxylates with unsaturated carbon chain with HLB higher than 12, e.g. Brij® 97 and Brij® 99, polyoxyethylene sorbitan alkyl esters with saturated C12 to C16 carbon chain and having HLB higher than 12; e.g. Tween® 20, polyoxyethylene sorbitan alkyl esters with unsaturated C18 carbon chain and having HLB higher than 9; e.g. Tween® 80, Tween® 81 ; and Tween® 85; alkyl glucosides e.g. decyl glucoside, and mixtures thereof.

[0070] Preferably, amphoteric surfactants are selected from betaines e.g. cocamidopropyl betaine (CAPB), sulfobetaine, cocoamphoacetate and mixtures thereof. More preferably, amophoteric surfactants are selected from betaine, sulfobetaine and mixtures thereof.

[0071] Further more preferably, amphoteric surfactants selected is CAPB. Amphoteric surfactants provide foam boost and improve sensorial properties of the composition. If the composition is formulated as a liquid wash-off composition, then it preferably comprises water in an amount from 50 to 95 wt%, more preferably from 60 to 90 wt%, even more preferably from 70 to 85 wt%, further more preferably from 75 to 80 wt% and still more preferably from 80 to 85 wt% water.

[0072] The compositions that are deodorants and / or antiperspirant products suitable to include the components of the present invention can be pump sprays, aerosol sprays, roll-ons, sticks, soft solids or gels made with conventional bases. When deodorant products, the same can comprise aluminium, nonaluminum active or both.

[0073] The composition described above preferably further comprises preservatives to protect against the growth of potentially harmful microorganisms. Examples of ingredients that may be used as preservatives in the composition include alkyl esters of para hydroxybenzoic acid, hydantoin derivatives, propionate salts, and a variety of quaternary ammonium compounds. More preferably, ingredients that may be used as preservative in the composition are sodium benzoate, iodopropynyl butyl carbamate, methylisothiazolinone, iodopropynylbutylcarbamate, phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate, ethylhexylglycerin, benzyl alcohol, alkane diols and mixtures thereof. The alkane diols that are suitable for use as preservative are C6-C12 alkanes that are vicinally substituted with hydroxy groups. Illustrative examples include 1 ,2- octane diol (caprylyl glycol), 2,3-octane diol, 1,2-nonane diol, 1 ,2-decane diol, 1,2-hexane diol, 3,4-octane diol, mixtures thereof or the like where caprylyl glycol is typically the most preferred. When present in the composition, preservatives are added preferably in an amount 0.001 to 5 wt%, more preferably 0.01 to 3 wt% and most preferably 0.02 to 2 wt%.

[0074] Preferably, the composition further comprises one or more skin brightening agents. Such one or more skin brightening agents may be selected from niacinamide, vitamin B6, vitamin C and its derivatives, vitamin E, glutathione precursors, resorcinol, phenyl ethyl resorcinol, 4- alkyl resorcinol e.g. 4-ethyl resorcinol, 4-butyl resorcinol, 4-hexyl resorcinol, and mixtures thereof.

[0075] Alternatively, the one or more skin brightening agents may also be selected from galardin, adapalene, ammonium lactate, arbutin, azelaic acid, butyl hydroxy anisole, butyl hydroxy toluene, citrate esters, deoxyarbutin, 1 ,3-diphenyl propane derivatives, 2,5-dihydroxybenzoic acid and its derivatives, 2-(4-acetoxyphenyl)-1,3-dithiane, 2-(4-hydroxyphenyl)-1 ,3-dithiane, ellagic acid, glucopyranosyl-1 -ascorbate, gluconic acid, glycolic acid, , 4-Hydroxy-5-methyl- 3[2H]-furanone, 4-hydroxyanisole and its derivatives, 4-hydroxybenzoic acid derivatives, hydroxycaprylic acid, inositol ascorbate, linoleic acid, magnesium ascorbyl phosphate, 5- octanoyl salicylic acid, salicylic acid, 3,4,5-trihydroxybenzyl derivatives, acetylglucosamine, symwhite, calcium pantothenate (Melano-block), seppiwhite and mixtures thereof.

[0076] Such one or more skin brightening agents may preferably be present in an amount from 0.1 to 10 wt%, more preferably from 1 to 7 wt% and even more preferably from 3 to 5 wt%.

[0077] Preferably, the composition further comprises a polymer. The polymer acts as thickener in the composition and improves sensorial properties of the composition. The polymer is preferably selected from the following classes:

[0078] • acrylate I R-methacrylate copolymer e.g. acrylates / steareth-20 methacrylate copolymer (commercially available as AculynTM 22) and acrylates / beheneth-25 methacrylate copolymer (commercially available as AculynTM 28),

[0079] • acrylate I R-methacrylate crosspolymer e.g. acrylates / steareth-20 methacrylate crosspolymer (commercially available as AculynTM 88),

[0080] • acrylates copolymer (commercially available as AculynTM 33),

[0081] • acrylate / R-alkyl acrylate crosspolymer e.g. acrylates / C10-C30 alkyl acrylate crosspolymer (commercially available as PemulenTM TR-2),

[0082] • copolymer of ammonium acryloyldimethyltaurate with vinyl pyrrolidone (commercially available as Aristoflex® AVC),

[0083] • copolymer of sodium acryloyldimethyltaurate with vinyl pyrrolidone (commercially available as Aristoflex® AVS); and

[0084] • crosspolymer of acryloyldimethyltaurate with R-alkyl acrylate and methyacrylate e.g. Ammonium acryloyldimethyltaurate / beheneth-25 methacrylate crosspolymer (commercially available as Aristoflex® HMB and Aristoflex® BLV); and mixtures thereof.

[0085] Alternatively, the composition may comprise cellulose-based thickeners such as hydroxyethyl cellulose, hydroxypropyl methyl cellulose and mixtures thereof. More preferably, the polymer is selected from acrylate I R-methacrylate copolymer, acrylates copolymer and mixtures thereof. Preferably, the composition comprises 0.1 to 5 wt%, more preferably 0.5 to 4.5 wt%, even more preferably 1 to 4 wt%, further more preferably from 1.5 to 3.5 wt%, still more preferably from 2 to 3 wt% of these polymers.

[0086] The composition may further comprise a range of other optional ingredients that include antioxidants, binders, buffering agents, colorants, astringents, fragrance, opacifying agents, conditioners, exfoliating agents, skin soothing agents, and skin healing agents.

[0087] Accordingly, in a preferred aspect, the present invention relates to a composition for use in protecting skin against harmful microorganisms wherein the composition comprises a prebiotic composition of: a. sugar alcohol; and b. a polyalkylene glycol, wherein the composition further comprises one or more activators of peroxisome proliferator- activated receptors.

[0088] Preferably, such harmful microorganisms are one or more of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Cutibacterium acnes (C. acnes).

[0089] In another preferred aspect, the present invention also relates to a method of protecting skin against harmful microorganisms comprising the steps of: i. applying a personal care composition comprising: a. a prebiotic combination of a sugar alcohol; and a polyalkylene glycol; and b. one or more activators of peroxisome proliferator-activated receptors; and ii. optionally, rinsing the skin.

[0090] Preferably, such harmful microorganisms are one or more of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa), Cutibacterium acnes (C. acnes). Preferably, the method is non-therapeutic or cosmetic in nature. In another preferred aspect, the present invention relates to a method of providing skin brightening comprising the steps of: i. applying a personal care composition comprising: a. a prebiotic combination of a sugar alcohol; and a polyalkylene glycol; and b. one or more activators of peroxisome proliferator-activated receptors; and ii. optionally, rinsing the skin.

[0091] Preferably, the method is non-therapeutic or cosmetic in nature.

[0092] In either of the preferred aspects describing a method above, the step of application, the step a., may be carried out simply by taking a suitable amount, e.g. 5 mL or 2 grams (depending on whether the composition is in liquid or solid form), of the composition on hands and gently spreading it over the area of skin. The composition, if required, may also be applied using an applicator in which case, a user is expected to use the applicator to carry out the step of applying the composition; and spread the composition using the applicator on the skin.

[0093] Further, the optional step b., where the composition applied in step a. is rinsed off using from the skin it was applied on to using copious amount of water.

[0094] If carried out, the step b., may preferably be carried out within 5 minutes, more preferably within 4 minutes, even more preferably within 3 minutes, further more preferably within 2 minutes and yet more preferably within 1 minute e.g. 30 seconds, or 15 seconds, from carrying out step a. Such optional step b. is particularly required to be carried out within 5 minutes, if the composition is formulated into a wash-off type of composition e.g. a face wash composition.

[0095] The following Examples are provided to further illustrate an understanding of the invention. The Examples are not intended to limit the scope of the claims. Examples

[0096] Experimental set-up for the prebiotics study was as follows:

[0097] Cell culture

[0098] Staphylococcus epidermidis ATCC 12228 was purchased from American Type Culture Collection (ATCC). The cultures were maintained on Tryptic Soy agar (TSA) (DIFCO) as specified by the ATCC.

[0099] Bacterial culture preparation

[0100] Bacterial cultures were streaked on TSA plates and incubated at 37°C for 18 to 22 hrs. After incubation, using a sterile loop the test bacteria were resuspended in saline and optical density (OD) (at 620 nm) was adjusted to 108CFU / mL respectively. The cultures were then diluted in saline to 106CFU / mL. The bacterial cultures (105CFU / mL) were inoculated into TSB medium with / without prebiotic combinations as shown in table 1 below. All tubes were incubated at 37°C for three days. After incubation, the supernatants were collected by centrifugation at 7000 rpm for 5 min and by passing it through 0.22 pm pore size filters.

[0101] Assay for measuring short chain fatty acids:

[0102] Short chain fatty acid contents of the supernatants were estimated using HPLC-UV. The sample preparation was done in water. The results were as shown in table 1 below.

[0103] Melanin content assay

[0104] Human primary melanocytes (Invitrogen, USA) were seeded at a density of 5 x 104cells per well into a 24-well plate. Post 24 h of incubation, cells were treated as shown in table 2 below; and where required, a PPAR activator, e.g. 12-HSA, was added to melanocytes; and the melanocytes were incubated further for 72 h at 5% CO2 / 37°C. After 72 h of incubation, cells were harvested; and melanin content was estimated by spectrophotometry at 405 nm with a microplate reader (Genios Pro, Tecan). Table 1:

[0105] •Molecular weight is 550 Daltons (Sigma Catalogue: 409510)].

[0106] The data in table 1 above shows that the combination of a sugar alcohol e.g. glycerol, with a polyalkylene glycol e.g. polyethylene glycol, boosted the secretion of the short fatty acids.

[0107] Thus, the combination acts as a prebiotic.

[0108] Further, melanocytes were treated as shown in table 2 below and melanin content was estimated as described earlier. The percentage melanin content was found to be as shown in table 2 below:

[0109] Table 2:

[0110] •Molecular weight is 550 Daltons (Sigma Catalogue: 409510)]. The data in table 2 above shows that when the combination of a sugar alcohol e.g. glycerol; and a polyalkylene glycol e.g. polyethylene glycol, was combined with a PPAR activator e.g. 12-HSA, improved melanin reduction was obtained. It is to be understood that the experiments described above were conducted in an invitro assay to evaluate the technical effect. It is expected that the concentrations to be actually used to prepare a composition for topical use would be vastly different. The concentrations could be orders of magnitude higher due to the following reasons that affect the difference in concentration in the bulk as compared to that at the cellular level. The composition may be formulated as an emulsion or a gel with very many additional ingredients. The concentration of the desired actives in the oil phase and in the water phase, is expected to be very different. They may also have very different physical and hydrodynamic properties like partition coefficients, diffusional rates, convective transport rates, rheological properties etc. Therefore, it is expected that the concentrations to be used when formulated as a composition would be very different from that at the cellular level.

Claims

CLAIMS1. Use of a combination of a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for protecting skin against harmful microorganisms.

2. Use of a combination of: a. a sugar alcohol; and b. a polyalkylene glycol, as a prebiotic, in a personal care composition comprising one or more activators of peroxisome proliferator-activated receptors, for providing skin brightening.

3. Use as claimed in claims 1 or 2 wherein the sugar alcohol is selected from glycerol, erythritol, xylitol, mannitol, sorbitol, galactitol, inositol, lactitol, and mixtures thereof.

4. Use as claimed in any one of claims 1 to 3 wherein the molecular weight of polyalkylene glycol is at least 200 Daltons.

5. Use as claimed in any one of claims 1 to 4 wherein the weight ratio of sugar alcohol to polyalkylene glycol is in the range from 1:20 to 20:1 , preferably 1:10 to 10:1 , preferably 1:2 to 2:1.

6. Use as claimed in any one of claims 1 to 5 wherein the polyalkylene glycol is selected from polyethylene glycol, polypropylene glycol, polybutylene glycol and mixtures thereof.

7. Use as claimed in claim 6 wherein the polyalkylene glycol is polyethylene glycol.

8. Use as claimed in any one of claims 1 to 7 wherein the composition comprises from 0.01 to 5 wt% of the one or more activators of peroxisome proliferator-activated receptors.

9. Use as claimed in any one of claims 1 to 8 wherein the one or more activators of peroxisome proliferator-activated receptors is selected from petroselinic acid, 10- hydroxystearic acid, 12-hydroxystearic acid, conjugated linoleic acid, ricinoleic acid and mixtures thereof.

10. Use as claimed in any one of claims 1 to 9 wherein the composition is in the form of a leave-on composition.

11. Use as claimed in any one of claims 1 to 9 wherein the composition is in the form of a wash-off composition further comprising from 3 to 80 wt% surfactant.

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