An antimicrobial cleansing composition

Abstract

The present invention relates to a personal cleansing composition. Particularly, it relates to a skin cleansing composition that provides improved antimicrobial benefit. This is achieved through a composition comprising a surfactant and select ester of carboxylic acid and mono alcohol along with an anti-microbial peptide or a booster thereof.

Description

[0001] P0001189 CPL

[0002] 1

[0003] AN ANTIMICROBIAL CLEANSING COMPOSITION

[0004] Field of the Invention

[0005] 5 The present invention relates to a personal cleansing composition. Particularly, it relates to a skin cleansing composition that provides improved antimicrobial benefit.

[0006] Background of the Invention

[0007] Frequent handwashing is one of the most effective and simple ways to prevent the spread of infection-causing germs. Several skin cleansing compositions e.g. a handwash or bodywash compositions are known in the art that provide antimicrobial benefit. Such skin cleansing compositions are available in the form of a solid e.g. a bar such as soap bar; and in the form of a liquid e.g. a liquid handwash or bodywash composition or in the form of powder, which can be diluted with water before use. Generally, antimicrobial benefit delivered by such skin cleansing 15 compositions is through use of one or more antimicrobial actives that may be included in such compositions. For example, skin cleansing composition comprising an antibacterial active e.g. triclosan, is known in the art.

[0008] However, there is still a need in the art for newer technologies that deliver improved

[0009] 20 effectiveness against bacteria. Further, skin cleansing is generally carried out only for about a few seconds to a few minutes. Thus, providing fast antimicrobial action is highly desired. The present inventors were looking to deliver improved efficacy in at least one of the above attributes through use of commonly used personal care actives that could interact synergistically to provide the high antimicrobial action.

[0010] 25

[0011] The present inventors have now found that a personal cleansing composition comprising a surfactant and select ester of carboxylic acid and mono alcohol along with an anti-microbial peptide or a booster thereof interacted synergistically to provide the desired improved antimicrobial benefit.

[0012] It is thus an object of the present invention to provide for a personal cleansing composition that delivers enhanced antimicrobial efficacy.

[0013] Summary of the Invention

[0014] 35 The first aspect of the present invention relates to an antimicrobial cleansing composition

[0015] comprising:P0001189 CPL

[0016] 2

[0017] (i) surfactant;

[0018] (ii) ester of C1 to C18 carboxylic acid and C1 to C10 mono alcohol;

[0019] (iii) an anti-microbial peptide (AMP) or an AMP booster; and

[0020] (iv) a cosmetically acceptable vehicle.

[0021] 5 Another aspect of the present invention relates to a method of killing bacteria comprising the steps of washing a surface with a composition of the first aspect preferably diluted with water for 15 seconds to 2 minutes followed by the step of rinsing the surface with water or wiping the surface to be substantially free of said composition.

[0022] Detailed Description of the Invention

[0023] 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 15 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 "from x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "from x to y", it is understood that all ranges combining the different endpoints are also contemplated. Unless specified otherwise, 20 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.

[0024] 25 For the purpose of the present invention, the terms ‘antimicrobial benefit’ or ‘antimicrobial effect’ or ‘antimicrobial efficacy’, may be used interchangeably and they denote the same meaning. Preferably, ‘antimicrobial benefit’ or ‘antimicrobial effect’ or ‘antimicrobial efficacy’ means reduction in number of microbes e.g. bacteria, fungi and viruses preferably bacteria. Such antimicrobial effect is obtained when the composition of the present invention is applied on to a surface preferably diluted with water; and a step of rinsing the surface is carried out within 2 minutes, preferably within one minute, more preferably within 30 second and sometimes as less as within 15 seconds from the step of applying the composition. The surface may be animate or inanimate. More preferably, the composition is applied to an animate substrate e.g. human skin. ‘Skin’ as used herein, preferably means to include skin on any part of the body e.g. face, neck, 35 chest, back, arms, underarms, hands, legs, buttocks and scalp.P0001189 CPL

[0025] 3

[0026] By ‘a cleansing composition’ as used herein, is meant to include a composition for topical application to skin, hair and / or scalp of mammals, especially humans. Such a composition is generally applied on to the desired topical surface of the body for a period of time from a few seconds to up to a few minutes generally after diluting with water. After this period of time of 5 application the composition is generally rinsed off with water or wiped away. It includes any product applied to a human body for also improving appearance, odour control or general aesthetics. The composition of the present invention can be in the form of a liquid, lotion, cream, foam, scrub, gel, shampoo, conditioner, handwash, facewash or bodywash product. Alternately and more preferably it may be in the form of a soap bar.

[0027] The composition of the invention comprises a surfactant in 25 to 85% by weight of the composition. Suitable surfactant is one or more of an anionic, non-ionic or amphoteric surfactant.

[0028] 15 The surfactant as per an especially preferred aspect of the present invention comprises an anionic surfactant. Anionic surfactant as per this invention may be a synthetic anionic surfactant or soap. The most preferred surfactant for use in the present invention is a soap.

[0029] Preferred synthetic anionic surfactants for inclusion in the composition of the invention are one 20 or more of isethionates, taurates, glycinates, alkyl sulfates, alkyl ether sulphates, succinates, sulphosuccinates, amphoacetates, sarconsinates, glutamates, a-olefin sulphonates, lactylates, methyl ester sulfonates and mixtures thereof. Further more preferred synthetic anionic surfactants are selected from, isethionates, taurates, glycinates, alkyl sulfates, alkyl ether sulfates (AES), alpha olefin sulfonates (AOS) and mixtures thereof. Even more preferably, the 25 synthetic anionic surfactant is selected from alkyl sulfates, alkyl ether sulfates and mixtures thereof. Most preferred synthetic anionic surfactant is an alkyl ether sulfate. Synthetic anionic surfactants are known to provide foam and cleansing action.

[0030] Examples of alkyl sulfates that may be used as anionic surfactant in the composition include sodium lauryl sulfate (SLS), sodium myristyl sulfate and mixtures thereof. Examples of AES that may be used as an anionic surfactant include anionic surfactants of the general formula: Ri-(OR’)n-O-SO3'M+, wherein:

[0031] Ri is saturated or unsaturated Cs-Cis, preferably C12-C16 alkyl chain; preferably, R1 is a saturated Cs-Cis, more preferably a saturated C12-C16 alkyl chain;

[0032] 35 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,P0001189 CPL

[0033] 4

[0034] M+is a suitable cation which provides charge neutrality, preferably ammonium, sodium, calcium, potassium, or magnesium, more preferably a sodium cation.

[0035] Examples of AES that may be used as anionic surfactants in the composition include sodium 5 lauryl ether sulfate (SLES), sodium myristyl ether sulfate and sodium palmityl ether sulfate 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.

[0036] Another class of anionic surfactants which is particularly desirable are alkyl isethionate (e.g., fatty acid esters of isethionate acid such as sodium lauroyl or sodium cocoyl isethionate) and alkyl taurate (e.g., alkyl taurate amides such as N-methyl taurate). Especially suitable is to include them as a surfactant mixture as they have the advantage that they are sulfate-free. Further, they offer the ability to formulate systems at neutral and slightly acidic pH.

[0037] 15 An especially preferred aspect relates to compositions comprising 5 to 20%, preferably 6 to 15% by weight of a surfactant system which comprises (a) alkali metal acyl isethionate, (b) alkali metal alkyl taurate.

[0038] Acyl isethionate surfactant is commonly produced by the direct esterification of a fatty acid (e.g., 20 C to Ci6 fatty acid such as lauric acid) and isethionate (e.g., HOCH2CH2SO3IVF’ where M+may be, for example, a sodium or potassium counterion) in a process commonly known as the “DEFI” process, where DEFI refers to directly esterified fatty acid isethionate. Preferred isethionate sulfonates include methyl cocoyl isethionate and lauroyl isethionate. They preferably have sodium or potassium as counterions.

[0039] 25

[0040] The other preferred anionic surfactant for inclusion in the composition of the invention are alkyl taurates, e.g., alkyl taurate amides. Such alkyl taurate amides may be made by reaction of a taurine; methyl taurine; or a corresponding taurate salt (e.g., NH2CH2CH2SO3 M+, where M+may be sodium or potassium counterion) with the appropriate fatty acid. Preferably alkyl taurate amides include sodium methyl cocoyl taurate and sodium methyl lauroyl taurate.

[0041] Synthetic anionic surfactant for use in the present invention may be included in 3.0 to 80 wt%, preferably 4.0 to 40 wt%, further more preferably 6 to 20 wt%.

[0042] When the anionic surfactant is a soap, it is generally delivered in the form of a soap bar. Soap 35 bars usually comprise 15 to 85% soap, preferably 20 to 75%, more preferably 25 to 70 and most preferably 30 to 70% by weight of the soap bar. It is also preferred that the personalP0001189 CPL

[0043] 5

[0044] washing composition comprises at least 15%, preferably at least 20%, more preferably at least 25% soap. The personal washing composition also further preferably comprises at most 75%, more preferably at most 60%, further more preferably at most 50% soap.

[0045] 5 The term soap means salt of fatty acid. Preferably, the soap is made C10 to C20 preferably C10 to C18 fatty acids. The cation may be an alkali metal, alkaline earth metal or ammonium ion, preferably alkali metals. Preferably, the cation is selected from sodium or potassium, more preferably sodium. The soap may be saturated or unsaturated. Saturated soaps are preferred over unsaturated soaps for stability. The oil or fatty acids may be of vegetable or animal origin. The soap may be obtained by saponification of oils, fats or fatty acids. The fats or oils generally used to make soap bars may be selected from tallow, tallow stearins, palm oil, palm stearins, soya bean oil, fish oil, castor oil, rice bran oil, sunflower oil, coconut oil, babassu oil, and palm kernel oil. The fatty acids may be from coconut, rice bran, groundnut, tallow, palm, palm kernel, cotton seed or soyabean.

[0046] 15

[0047] The fatty acid soaps may also be synthetically prepared (e.g. by the oxidation of petroleum or by the hydrogenation of carbon monoxide by the Fischer-Tropsch process). Resin acids, such as those present in tall oil, may also be used. Naphthenic acids may also be used.

[0048] 20 Soap in combination with a synthetic surfactant may also be included and such a formulation is often called a soap-syndet formulation. In a soap syndet formulation soap may be included in 0.1 to 30%, preferably from 1 to 25%, further more preferably from 5 to 20 % by weight of the composition.

[0049] 25 Preferably, the composition may further comprise 0.1 to 40 wt% an amphoteric surfactant, a non-ionic surfactant or mixtures thereof. They provide foam boost and improve sensorials of the composition. Preferably, amphoteric surfactants are selected from the class of betaines, sultaines, and amine oxides,. Preferred examples are cocam idopropyl betaine (CAPB), cocamide monoethanolamide (CMEA), cocoamphoacetate and mixtures thereof. When included the composition preferably comprises 0.1 to 20 wt%, more preferably from 1 to 10 wt% amphoteric surfactant.

[0050] Suitable nonionic surfactants include addition products of ethylene oxide and / or propylene oxide with fatty alcohols, fatty acids and fatty amines. Any of the alkoxylated materials of the

[0051] 35 particular type described hereinafter can be used as the nonionic surfactant. Preferably the nonionic surfactant has an HLB of from about 7 to about 20. Non-ionic surfactant of theP0001189 CPL

[0052] 6

[0053] polyglucoside type may also be used. If included, the nonionic surfactant is present in an amount from 0.01 to 10 wt.%, more preferably 0.1 to 5 wt.%, based on the total weight of the composition.

[0054] 5 The composition of the invention comprises an ester of C1 to C18 carboxylic acid and C1 - C10 mono alcohol. Said carboxylic acid is preferably a C1 to C12, more preferably a C2 to C5, further more preferably a C2 to C4 carboxylic acid. Said mono alcohol is preferably a C2 to C8, more preferably a C2 to C4 mono-alcohol. The ester is preferably selected from one or more of mono-ethyl citrate, diethyl citrate, triethyl citrate, tributyl citrate, dibutyl adipate, diisopropyl 10 adipate, dioctyl adipate, ethyl lactate and isoamyl laurate. The above compounds have the respective structures as given below:

[0055]

[0056] Di-Ethyl Citrate

[0057] 20

[0058]

[0059] Triethyl citrateP0001189 CPL

[0060] 7

[0061]

[0062] 10

[0063] Dioctyl adipate (here the octyl chain may be straight chain or branched)

[0064]

[0065] ethyl lactateP0001189 CPL

[0066]

[0067] isoamyl laurate

[0068] The preferred esters of C1 to C18 carboxylic acid and C1 to C10 mono alcohol for inclusion in the composition of the invention are mono ethyl citrate, diethyl citrate, triethyl citrate, isoamyl 5 laurate or tributyl citrate preferably triethyl citrate. The ester of C1 to C18 carboxylic acid and C1 to C10 mono alcohol is included in 0.01 to 10%, preferably in 0.1 to 5.0%, further more preferably 0.2 to 4 wt%, even further more preferably 0.3 to 3 wt% by weight of the composition. The composition as per the invention comprises an anti-microbial peptide (AMP) or an AMP booster. When an AMP is included it may be one or more of LL37, Psoriacin, HBD1, or HBD3, preferably LL37. When an AMP is included, it is present in 0.000001 to 0.1 wt% of the composition.

[0069] Alternately, an AMP booster may be included. Suitable AMP boosters are chosen from one or more of hydroxy stearic acid; nicotinamide; isomer of nicotinamide, cycloalkyl derivatives of 15 nicotinamide, Vitamin A, Vitamin C, linseed oil, moringa oil, soyabean oil, tea polysaccharide, tetrahydroxypropyl ethylenediamine and Vitamin E. Preferred AMP boosters are selected from one or more of hydroxystearic acid; nicotinamide; isomer of nicotinamide, cycloalkyl derivatives of nicotinamide, Vitamin A, Vitamin C, Vitamin E and linseed oil. Most preferred AMP boosters are one or more of hydroxystearic acid, nicotinamide, Vitamin C and Vitamin E. An AMP 20 booster as per this invention is meant a compound which when applied on to the skin of a living being (e.g. a human being) produces enhanced levels of AMPs on skin.

[0070] It is preferred that the hydroxystearic acid is 10- hydroxy stearic acid, 12- hydroxy stearic acid or tri hy doxy stearic acid (e.g. 9, 10,13-tri hydroxy stearic acid) or trihydroxy stearin or compounds 25 that yield one or more molecules of hydroxystearic acid or hydroxystearate on their breakdown like mono, di or tri ester of glycerol with hydroxy stearic acid. Thus, hydroxystrearic acid by way of this invention also includes salts and esters thereof. Of these, 10- hydroxy stearic acid, 12- hydroxystearic acid and 9, 10,13-tri hydroxy stearic acid are more preferred. 12- hydroxy stearic acid (12-HSA) is most preferred. 12-HSA has the structure as given below:

[0071] 30

[0072]

[0073] P0001189 CPL

[0074] 9

[0075] A preferred AMP booster is nicotinamide (which is also known as niacinamide) which is a Vitamin B3 compound. Other vitamin B3 compound which may be used are niacin or nicotinic acid. Isomers of nicotinamide which may be used include isonicotinamide or picolinamide. Cycloalkyl derivatives of nicotinamide which may be used have 4 to 6 carbon atoms in the 5 cycloalkyl group, e.g. are one or more of n-cyclobutyl nicotinamide, n-cyclopentyl nicotinamide, and n-cyclohexyl nicotinamide. The most preferred Vitamin VB3 compound is niacinamide. Niacinamide also known as pyridine-3-carboxamide is the active, water soluble form of vitamin B3.

[0076] Vitamin C or it derivatives may also be used as an AMP booster in the composition of the invention. Vitamin C or its derivative for use may be selected from one or more of ascorbic acid, sodium ascorbyl phosphate, 3-0-ethyl ascorbic acid, ascorbyl methylsilanol pectinate, magnesium ascorbyl phosphate, ascorbyl glucoside, and tetrahexyldecyl ascorbate; preferably ascorbic acid or sodium ascorbyl phosphate.

[0077] 15

[0078] The composition of the present invention comprises a Vitamin A compound as the AMP booster which is also known as a retinoid. Typically, the retinoid is selected from retinyl ester, retinol, retinal, retinoic acid or a mixture thereof. More preferably the retinoid comprises retinol, retinyl ester, or a mixture thereof and even more preferably the retinoid is selected from retinol, retinyl 20 ester, or a mixture thereof. Of these retinyl esters are preferred. Suitable retinyl esters for use in the present invention are retinyl palmitate, retinyl propionate, retinyl acetate, retinyl linoleate, retinyl oleate, or a mixture thereof. Most preferred are retinyl palmitate, retinyl acetate, retinyl propionate, or a mixture thereof.

[0079] 25 The composition of the invention preferably comprises 0.00001% to 5 wt%, more preferably 0.00003 to 1 wt% AMP booster.

[0080] The composition of the invention preferably additionally comprises a chelating agent. The preferred chelating agent for inclusion in the composition of the invention may be selected from one or more of a compound belonging to the amino carboxylate or phosphonate group.

[0081] Preferred chelating agents are tetra sodium etidronate, tetra sodium EDTA (ethylene diamine tetra acetic acid) or mixtures thereof.

[0082] 35 The chelating agent is preferably included in 0.001 to 10%, preferably 0.01 to 5% by weight of the composition.P0001189 CPL

[0083] 10

[0084] The composition of the invention comprises a cosmetically acceptable vehicle. The cosmetically acceptable vehicle comprises one or more of a substance which can deliver the composition as a cleansing composition I wash-off composition. This substance may be one or more of a surfactant, polymer, emollient or water, preferably a surfactant and / or water.

[0085] 5 The composition of the invention may be delivered as a composition for cleansing the topical surfaces of the human body preferably the skin surface. The composition may be in the form of a liquid, gel, cream, lotion, powder or a bar, all of which are conventional forms of skin cleansing compositions.

[0086] By a soap bar composition is meant a cleansing composition comprising soap which is in the form of a shaped solid. The soap bar of the invention is especially useful for personal cleansing. When the composition of the invention is a soap bar, the cosmetically acceptable vehicle comprises water, structuring agent, electrolyte, polymer or combinations thereof.

[0087] 15 The soap bar may additionally comprise synthetic surfactants selected from one or more from the class of anionic, non-ionic, cationic or zwitterionic surfactants, preferably from anionic surfactants.

[0088] Composition of the invention preferably includes starch. When included it is present in 0.01 to 20 25%, more preferably 5 to 22%, further more preferably 10 to 20%, even further more preferably 10 to 18% by weight of the composition. Starch from any source such as corn, potato, sweet potato, rice, or wheat may be used but it is preferably corn starch.

[0089] The composition of the present invention is preferably in the form of a shaped solid for example 25 a bar. The cleaning soap composition is a wash off product that generally has sufficient amount of surfactants included therein that it is used for cleansing the desired topical surface e.g. the whole body, the hair and scalp or the face. It is applied on the topical surface and left thereon only for a few seconds or minutes and washed off thereafter with water.

[0090] The soap bar of the invention preferably comprises water in the range of 14 to 40 wt%. In preferred aspects the soap bar preferably comprises at least 14%, more preferably at least 18%, further more preferably at least 22% water by weight of the composition. The soap bar further preferably comprises at most 40%, more preferably at most 35%, further more preferably at most 30% water by weight of the composition. If the composition is in liquid form water is 35 included in 40 to 95% by weight of the composition.P0001189 CPL

[0091] 11

[0092] The soaps bar composition may optionally comprise 0.1 to 15%, preferably 0.2 to 12% by weight of free fatty acids. By free fatty acids is meant a carboxylic acid comprising a hydrocarbon chain and a terminal carboxyl group bonded to an H. Suitable fatty acids are C8 to C22 fatty acids. Preferred fatty acids are C12 to C18, preferably predominantly saturated, 5 straight-chain fatty acids. However, some unsaturated fatty acids can also be employed.

[0093] The composition preferably comprises a polyhydric alcohol (also called polyol) or mixture of polyols. Polyol is a term used herein to designate a compound having multiple hydroxyl groups (at least two, preferably at least three) which is highly water soluble. Many types of polyols are available including: relatively low molecular weight short chain polyhydroxy compounds such as glycerol and propylene glycol; sugars such as sorbitol, mannitol, sucrose and glucose; modified carbohydrates such as dextrin and maltodextrin, and polymeric synthetic polyols such as polyalkylene glycols, for example polyoxyethylene glycol (PEG) and polyoxypropylene glycol (PPG). Especially preferred polyols are glycerol, sorbitol and their mixtures. Most preferred polyol is glycerol. In a preferred embodiment, the bars of the invention comprise 0 to 8%, 15 preferably 1 to 7.5% by wt. polyol.

[0094] The soap bar composition generally comprises electrolyte and water. Electrolytes as per this invention include compounds that substantially dissociate into ions in water. Electrolytes as per this invention are not an ionic surfactant. Suitable electrolytes for inclusion in the soap making 20 process are alkali metal salts. Preferred alkali metal salts include sodium sulfate, sodium chloride, sodium acetate, sodium citrate, potassium chloride, potassium sulfate, sodium carbonate and other mono or di or tri salts of alkaline earth metals, more preferred electrolytes are sodium chloride, sodium sulfate, sodium citrate, potassium chloride and especially preferred electrolyte is sodium chloride, sodium sulphate, tri-sodium citrate or a combination thereof. For 25 the avoidance of doubt, it is clarified that the electrolyte is a non-soap material. Electrolyte is preferably included in 0.1 to 6%, more preferably 0.5 to 6%, even more preferably 0.5 to 5%, further more preferably 0.5 to 3%, and most preferably 1 to 3% by weight of the composition. It is preferred that the electrolyte is included in the soap bar during the step of saponification to form the soap.

[0095] The various optional ingredients that make up the final soap bar composition are as described below.

[0096] The total level of the adjuvant materials used in the bar composition generally is in an amount 35 not higher than 50%, preferably 1 to 50%, more preferably 3 to 45% by wt. of the soap bar composition.P0001189 CPL

[0097] 12

[0098] The adjuvant system may optionally include insoluble particles comprising one or a combination of materials. By insoluble particles is meant materials that are present in solid particulate form and suitable for personal washing. Preferably, there are mineral (e.g., inorganic) or organic particles.

[0099] 5

[0100] The insoluble particles should not be perceived as scratchy or granular and thus should have a particle size less than 300 microns, more preferably less than 100 microns and most preferably less than 50 microns.

[0101] Preferred inorganic particulate material includes talc and calcium carbonate. Talc is a magnesium silicate mineral material, with a sheet silicate structure and a composition of Mg3Si4(OH)22, and may be available in the hydrated form. It has a plate-like morphology, and is essentially oleophilic / hydrophobic, i.e. , it is wetted by oil rather than water.

[0102] 15 Calcium carbonate or chalk exists in three crystal forms: calcite, aragonite and vaterite. The natural morphology of calcite is rhombohedral or cuboidal, acicular or dendritic for aragonite and spheroidal for vaterite.

[0103] Examples of other optional insoluble inorganic particulate materials include aluminates, 20 silicates, phosphates, insoluble sulfates, borates and clays (e.g., kaolin, china clay) and their combinations.

[0104] Organic particulate materials include cellulose; synthetic polymers such as various polymer lattices and suspension polymers; insoluble soaps and mixtures thereof.

[0105] 25

[0106] Bar compositions preferably comprise 0.1 to 25% by wt. of bar composition, preferably 5 to 15 by wt. of these mineral or organic particles.

[0107] It is preferred that the compositions of the invention comprise polymers. Polymers of the acrylate class are especially preferred. Preferred bars include 0.05 to 5% acrylates. More preferred bars include 0.01 to 3% acrylates. Examples of acrylate polymers include polymers and copolymers of acrylic acid crosslinked with polyallylsucrose as described in US Patent 2,798,053 which is herein incorporated by reference. Other examples include polyacrylates, acrylate copolymers or alkali swellable emulsion acrylate copolymers, hydrophobically modified 35 alkali swellable copolymers, and crosslinked homopolymers of acrylic acid. Examples of suchP0001189 CPL

[0108] 13

[0109] commercially available polymers are: ACLILYN®, CARBOPOL®, and CARBOPOL® Ultrez grade series.

[0110] An opacifier may be optionally present in the personal care composition. When opacifiers are 5 present, the cleansing bar is generally opaque. Examples of opacifiers include titanium dioxide, zinc oxide and the like. A particularly preferred opacifier that can be employed when an opaque soap composition is desired is ethylene glycol mono- or di-stearate, for example in the form of a 20% solution in sodium lauryl ether sulphate. An alternative opacifying agent is zinc stearate. The product can take the form of a water-clear, i.e. transparent soap, in which case it will not contain an opacifier.

[0111] The pH of preferred soaps bars of the invention is from 8 to 11 , more preferably 9 to 11.

[0112] A preferred bar may additionally include up to 30 wt% benefit agents. Preferred benefit agents include moisturizers, emollients, sunscreens and anti-ageing compounds. The agents may be 15 added at an appropriate step during the process of making the bars. Some benefit agents may be introduced as macro domains.

[0113] Other optional ingredients like anti-oxidants, perfumes, colourants, deodorants, dyes, enzymes, foam boosters, lathering agents, pearlescers, skin conditioners, stabilizers or superfatting 20 agents, may be added in suitable amounts in the process of the invention. Preferably, the ingredients are added after the saponification step.

[0114] Another aspect of the present invention relates to a method of killing bacteria comprising the steps of washing a surface with a composition of the first aspect preferably diluted with water for 25 15 seconds to 2 minutes followed by the step of rinsing the surface with water or wiping the surface to be substantially free of said composition. By “substantially free of said composition” is meant that there are no visible residues of the composition or any visible foaming during the last stage of rinsing the surface with water. The method is preferably non-therapeutic.

[0115] 30 The invention will now be illustrated with the help of the following non-limiting examples.P0001189 CPL

[0116] 14

[0117] A-D, 1-2: Effect of combination of an AMP (LL-37) with tri ethyl citrate on log reduction of S. hominis and S. aureus

[0118] 5

[0119] Compositions as shown in Table -1 below were prepared and the log reduction of S. hominis, S. aureus and E.coli bacteria was measured using the procedure as given below:

[0120] Test Organisms Used: S. aureus ATCC 6538, S. hominis ATCC 27844 and Escherichia coli ATCC 10536

[0121] The test organisms were inoculated from glycerol stock to Tryptic Soy Agar (TSA) +1% Yeast Extract (YE) slants and incubated at 37°C aerobically for 24 hours. These slants were further used to streak fresh TSA+1 %YE agar plates for the next passage of the cultures which were 15 then incubated at 37°C for ~16 hrs before performing the assay.

[0122] On the day of performing the assay, one loopful of the respective culture plate was taken and dissolved in 10mM Sodium Phosphate buffer and the optical density was adjusted using a spectrophotometer to obtain 108CFU / ml of the bacteria. This culture was serially diluted to get 20 ~ 106CFU / ml to perform the assay in a multi-well plate. To the assay plate, the bacterial suspension and 100mM buffer were added to each well so that the final concentration was uniform in all the reactions. LL-37 stock was prepared at 1mg / ml and a working stock of 10 pg / ml was prepared by dilution in distilled water and were added to the reaction mix as per the required concentration. 1% stock solution of TEC was prepared in sterile distilled water from 25 which the volume was taken according to the concentration required. The total volume of the reaction in each well was made up to 300 pl with water and each reaction was done in duplicates. After a contact time of 4 hours at 37° C, using spread plate method the samples were plated on pre-prepared TSA+1 % YE agar plates in requisite dilutions. The serial dilutions of the samples were made in D / E neutralizer, in a microtitre plate. 100 pl volume of desired dilutions were spread plated onto prepared plates. Plates were incubated aerobically up to 24hrs. Post incubation, the colonies were counted and the log reduction was calculated as compared to the culture control.

[0123] The data is summarized in table -1 below:

[0124] 35P0001189 CPI- 15

[0125] Table - 1

[0126]

[0127] 5 The data in the table - 1 indicates that compositions as per the invention (Examples 1 and 2) provide for vastly superior bacteria reduction as compared to respective individual actives (Examples A-D).

[0128] Example E-H, 3-12: Effect of combination of an AMP (LL-37) with triethyl citrate in combination 10 with an AMP booster on log reduction of S. aureus

[0129] Compositions as shown in Table -2 below were prepared and the log reduction of S. hominis was measured using the procedure as given hereinabove.

[0130] 15 The data is summarized in table -2 below:P0001189 CPL

[0131] 16

[0132] Table -2

[0133]

[0134] 5 The data in Table - 2 above (Example 3 in comparison to Examples E and F and Example 8 in comparison to Example G and H) reproduces the result as shown earlier in Table -1. Further, from Examples 4 to 12 it is clear that a combination of an ester (e.g TEC) with several AMP boosters in the presence of LL-37 (an AMP which is normally present on skin), at various concentrations, results in further enhanced efficacy.

[0135] 10

[0136] It is to be understood that the experiments described above were conducted under conditions which mimic actual washing scenarios where the concentration of the active could be an order or two magnitude lower than the composition claimed in the present invention. This is due to the actual washing condition where the composition is diluted with large amounts of water during

Claims

P0001189 CPL17CLAIMS1. An antimicrobial cleansing composition comprising:(i) 25 to 85 wt% surfactant;(ii) 0.01 to 10 wt% ester of C1 to C18 carboxylic acid and C1 to C10 mono alcohol; (iii) an anti-microbial peptide (AMP) or an AMP booster; and(iv) a cosmetically acceptable vehicle;wherein the AMP booster is selected from one or more of hydroxy stearic acid, nicotinamide, isomer of nicotinamide, cycloalkyl derivatives of nicotinamide, Vitamin A, Vitamin C, linseed oil, moringa oil, soyabean oil, tea polysaccharide, tetrahydroxypropyl ethylenediamine, and Vitamin E;wherein the cyclo alkyl derivatives of nicotinamide have 4 to 6 carbon atoms in the cyclo alkyl group.

2. A composition as claimed in claim 1 wherein said surfactant is soap.

3. A composition as claimed in claim 2 comprising 25 to 75 wt% soap.

4. A composition as claimed in any one of the preceding claims wherein said ester of C1 to C18 carboxylic acid and C1 to C10 mono alcohol is selected from one or more of monoethyl citrate, diethyl citrate, triethyl citrate, tributyl citrate, dibutyl adipate, diisopropyl adipate, ethyl lactate, isoamyl laurate and dioctyl adipate.

5. A composition as claimed in claim 4 wherein said ester of C1 to C18 carboxylic acid and C1 to C10 mono alcohol is selected from one or more of mono-ethyl citrate, diethyl citrate, triethyl citrate, dibutyl adipate and isoamyl laurate.

6. A composition as claimed in any one of the preceding claims wherein the AMP booster is selected from one or more of hydroxy stearic acid, nicotinamide, Vitamin C, and Vitamin E.

7. A composition as claimed in any one of the preceding claims comprising 0.00001% to 5 wt% AMP or AMP booster.P0001189 CPL188. A composition as claimed in any one of the preceding claims wherein the cosmetically acceptable vehicle comprises water, structuring agent, electrolyte, polymer or combinations thereof.

9. A composition as claimed in any one of the preceding claims comprising 0.01 to 25 wt% starch.

10. A composition as claimed in any one of the preceding claims in the form of a soap bar.

11. A soap bar composition as claimed in claim 10 comprising 14 to 40 wt% water.

12. A method of killing bacteria comprising the steps of washing a surface with a composition as claimed in any one of the preceding claims, preferably diluted with water for 15 seconds to 2 minutes, followed by the step of rinsing the surface with water or wiping the surface to be substantially free of said composition.

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