WO2025061420A1

WO2025061420A1 - An antimicrobial cleansing composition

Info

Publication number: WO2025061420A1
Application number: PCT/EP2024/073846
Authority: WO
Inventors: Sameer Keshav Barne; Karthika BEENA; Akshatha NARASIMHAMURTHY; Maya Treesa Saji
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV; Conopco Inc
Priority date: 2023-09-20
Filing date: 2024-08-26
Publication date: 2025-03-27
Anticipated expiration: 2026-03-20

Abstract

The present invention relates to a personal cleansing composition. Particularly, it relates to a skin cleansing composition that delivers improved antimicrobial benefit. This has been achieved through a combination of sodium laurate with two activity enhancers, at least one of which is selected from a list of known chelating agents.

Description

AN ANTIMICROBIAL CLEANSING COMPOSITION

Field of the Invention

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

Background of the Invention

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 compositions is delivered by 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.

However, there is still a need in the art for newer technologies that deliver improved effectiveness against both gram positive bacteria as well as gram negative bacteria. Further, skin cleansing is generally carried out only for about a few seconds to a few minutes. Thus, providing fast antimicrobial action is also 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.

The present inventors have now found that a personal cleansing composition comprising sodium laurate along with at least two activity enhancers, at least one of which is selected from a list of chosen chelating agents interacted synergistically to provide the desired improved antimicrobial benefit.

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

The first aspect of the present invention relates to an antimicrobial cleansing composition comprising

(i) salt of lauric acid; and

(ii) at least two activity enhancers selected from amino carboxylates, polyhydroxy carboxylates, polyphosphates, and dicarboximides; and (iii) a cosmetically acceptable vehicle; wherein each of the activity enhancers is included in 0.005 to 5% by weight of the composition; and wherein at least one activity enhancer is an amino carboxylate selected from trisodium methyl glycine diacetate (MGDA) or L-glutamic acid N, N-diacetic acid tetrasodium salt (GLDA).

Another aspect of the present invention relates to a method of killing both gram negative and gram positive bacteria comprising the step of washing a surface with a composition of the first aspect preferably diluted with water for at least 15 seconds to 2 minutes followed by the step of rinsing the surface with water or wiping the surface to be substantially free of the composition.

Detailed Description of the Invention

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 "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, 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.

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 preferably applied on to a surface that may be an inanimate or animate surface; 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. 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, chest, back, arms, underarms, hands, legs, buttocks and scalp.

The composition of the invention comprises a salt of lauric acid. It can also be called a laurate soap. Lauric acid is a fatty acid which is generally part of the distilled fatty acid stock which may be made from any oil or fat feedstock. They are 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. Coconut oil is generally known to be high in lauric acid and therefore soap made from coconut oil contains high amount of salt of lauric acid. Alternately the salt of lauric acid may be procured from producers who fractionate the fatty acid and then neutralise it to prepare salt of fatty acid which is very high in salt of lauric acid. 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 composition preferably comprises 0.5 to 20%, preferably 5 to 10% salt of lauric acid by weight of the composition.

The composition of the invention comprises at least two activity enhancers which are chosen from a list of compounds of the amino carboxylate, polyhydoxy carboxylate, polyphosphate class and dicarboximide class. Preferred are the ones having chelating properties. When an amino carboxylate is selected, it is preferably one having tertiary nitrogen. Preferred amino carboxylate is chosen from one or both of trisodium methyl glycine diacetate (MGDA) and L-glutamic acid N, N-diacetic acid tetrasodium salt (GLDA). The preferred activity enhancers are trisodium methyl glycine diacetate (MGDA), L-glutamic acid N, N-diacetic acid tetrasodium salt (GLDA), sodium gluconate, hexametaphosphate (HMP) and tetra-acetyl ethylenediamine (TAED). It is particularly preferred that the composition comprises two activity enhancers.

Compositions of the invention may comprise an activity enhancer which may be a polyphosphate or a water-soluble salt thereof. Preferably the polyphosphate is an inorganic polyphosphate. It preferably has an average chain length of at least 4. It may be arranged in a linear or cyclic configuration, preferably in a cyclic configuration. The inorganic polyphosphates may also be of branched form. It is preferred that the inorganic polyphosphate is selected from one or more of tripolyphosphate 3, tetrapolyphosphate 4, and hexametaphosphate 6. Polyphosphates larger than tetrapolyphosphate usually occur as amorphous glassy materials. Preferred in this invention is hexametaphosphate, particularly sodium hexametaphosphate. Any binary combination of the activity enhancers may be used but preferred ones are the following: GLDA + HMP, GLDA + sodium gluconate, GLDA + TAED, MGDA + HMP, MDGA + Na- Gluconate, MGDA + TAED, and MGDA + GLDA. More preferred binary combinations of the activity enhancers are the following: GLDA + HMP, GLDA + sodium gluconate, GLDA + TAED, MGDA + HMP, MDGA + Na-Gluconate, and MGDA + TAED. Each of the activity enhancers are included in 0.005 to 5%, preferably 0.01 to 1 % by weight of the composition.

Without wishing to be bound by theory the inventors believe that the first activity enhancer e.g. the amino acid-based chelators like GLDA and MGDA could bind to the divalent ions that holds the adjacent LPS molecules on the bacterial membrane and leads to destabilization of the bacterial membrane. This allows a faster entry of other active molecules to the bacteria leading to an enhanced bacterial kill.

It is particularly preferred that the composition is substantially free of a bleaching agent. Thus, the composition preferably comprises less than 1 wt%, more preferably less than 0.1 wt%, even more preferably less than 0.05 wt%, and further more preferably less than 0.01 wt% of bleaching agent. Still more preferably, the bleaching agent is only present in technically irrelevant amounts and ideally bleaching agent is absent from the composition.

Bleaching agent is a compound which can cause a bleaching action on a surface. Such agents are generally of the chlorine or peroxide type, preferably peroxide type. By a peroxide type bleaching agent is meant one which comprises a source of hydrogen peroxide. Compounds of this class include perborate, percarbonate, peracid and persulphate salts. They could also be of the persilicate or perphosphate class. The bleaching agent is generally an alkali salt preferably a sodium salt.

More preferably the composition is substantially free of a silver compound.

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.

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 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.

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, soap other than salt of lauric acid, structuring agent, electrolyte, polymer or combinations thereof. When the soap bar of the present invention is for personal washing application it comprises 15 to 75% soap (other than the salt of lauric acid), preferably 20 to 75%, more preferably 25 to 70 and most preferably 50 to 70% by weight of the soap bar. It is also preferred that the personal washing composition comprises at least 15%, preferably at least 20%, more preferably at least 25% soap other than the salt of lauric acid by weight of the composition. The personal washing composition also futher preferably comprises at most 50%, more preferably at most 60%, further more preferably at most 75% soap other than salt of lauric acid by weight of the composition.

The term soap means salt of fatty acid. Preferably, the soap (other than the salt of lauric acid) is soap of C10 -C11 and C14 to C24 preferably soap of C10-C11 and C14 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.

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.

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. The composition of the present invention is preferably in the form of a shaped solid for example 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 copious amounts of water.

The soap bar of the invention is 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.

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, straight-chain fatty acids. However, some unsaturated fatty acids can also be employed.

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 hydrolyzed starch, 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%, preferably 1 to 7.5% by wt. polyol.

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 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, sodium citrate or a combination thereof. For 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.

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

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

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.

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.

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.

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.

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

Organic particulate materials include: insoluble polysaccharides such as highly crosslinked or insolubilized starch (e.g., by reaction with a hydrophobe such as octyl succinate) and cellulose; synthetic polymers such as various polymer lattices and suspension polymers; insoluble soaps and mixtures thereof.

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. 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 alkali swellable copolymers, and crosslinked homopolymers of acrylic acid. Examples of such commercially available polymers are: ACULYN®, CARBOPOL®, and CARBOPOL® Ultrez grade series.

An opacifier may be optionally present in the personal care composition. When opacifiers are 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.

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

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 added at an appropriate step during the process of making the bars. Some benefit agents may be introduced as macro domains.

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

Another aspect of the present invention relates to a method of killing both gram negative and gram positive bacteria comprising the step of washing a surface with a composition of the first aspect preferably diluted with water for at least 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. The method is preferably non-therapeutic.

The invention will now be illustrated with the help of the following non-limiting examples. Examples

Examples A-E,1 : Effect of the composition on the log reduction of E.coli.

Combination of actives as shown in Table -1 below were used to measure the log reduction of E.coli 10536 after one minute of contact time at 40 °C and at a pH of 9.8.

The following protocol was used to evaluate biocidal activity.

In-vitro time-kill protocol - ASTM 2783

Preparation of the bacterial culture

Escherichia. coli ATCC 10536 was used in the study to represent gram negative bacteria and Staphylococcus aureus ATCC 6538 was used to represent gram positive bacteria. The bacteria were grown overnight on Trypticase soya agar (TSA) plate. The bacterial cell density was then adjusted at 620 nm to a pre-calibrated optical density to get the final count of 10⁹ cfu/ml in saline (0.86% NaCI) by using a spectrophotometer.

Assay Protocol: ASTM International E2783-16 is a standard test method for assessment of antimicrobial activity for water miscible compounds using a Time -Kill procedure.

9.9 mL of the comparative composition was taken in a sample container to which 0.1 mL of bacterial culture was added just before performing the assay and mixed well to obtain a mixture at 40°C. A timer was started immediately after the addition of the culture. The mixture was kept for a specific contact time of either 30 seconds, 1 minute or 2 minutes.

At the end of the contact time the antibacterial activity of the comparative composition was neutralized immediately, by addition of 1 mL of the above mixture to 9 mL of an appropriate neutralizing broth which is validated for the test system. The neutralized samples were then serially diluted upto 5 dilution in neutralizer broth and plated on TSA (40gpl - Difco) in duplicates.

The above mentioned assay protocol was similarly followed for all other comparative and preferred compositions.

For the assay, the control used was a mixture prepared by addition of 0.1 mL of bacterial culture to 9.9 mL of saline; the mixture was then serially diluted and plated on TSA. After solidification of the TSA plates, the plates were incubated at 37°C for 48 hours. The colonies on the plates were counted. The log reduction was calculated by comparing with the control.

The data is summarized in Table -1 below:

Table - 1

The data in table -1 above indicates that composition as per the invention (Example -1) provides for vastly improved log reduction as compared to the individual ingredients or subset combinations.

Example F-G,2: Effect of the composition at different concentrations on the log reduction o E.coli.

Combination of actives as shown in Table -2 below were used to measure the log reduction of E.coli 10536 after one minute of contact time at 40 °C and at a pH of 9.8.

The procedure used was the same as in Table -1 .

The data is summarized in Table -2 below:

Table - 2

The data in table -2 above indicates the same trends as in Table -1 at higher concentration of the activity enhancers.

Example H-J and 3: Effect of using a different activity enhancer on the log reduction of E.coli. Combination of actives as shown in Table -3 below were used to measure the log reduction of E.coli 10536 after one minute of contact time at 40 °C and at a pH of 9.8.

The procedure used was as described hereinabove.

The data is summarized in Table -3 below: Table - 3

The data in table -3 above indicates that composition as per the invention (Example -3) provides for vastly improved log reduction as compared to subset combinations.

Example K-L and 4,5: Effect of using yet another activity enhancer on the log reduction of S. aureus in a soap bar composition.

A soap bar noodle having the composition as given in Table - 4A below was taken. Table - 4A

The above soap noodle was used to blend into a soap bar composition as given in Table 4B below: Table 4B:

Minors include perfume and colour.

Actives as shown in Table -5 was evenly mixed with the soap composition of Table -4B. The soap sample for antimicrobial analysis was prepared as 8% soap slurry at 50°C and the testing was carried out at 40°C following the above mentioned method of ASTM E2783 -16 used to measure the log kill of S. aureus 6538 after 30 seconds of contact time.

The data is summarized in Table -5 below:

Table - 5

The data in table -5 above indicates that composition as per the invention (Example -4) provides for vastly improved log reduction of S. aureus bacteria as compared to base soap and a subset combination.

Example M,N,5: Effect of the composition of the invention on the log reduction of E.coli in a soap bar composition.

A soap composition as given in Table - 4B above was taken.

Actives as shown in Table -6 was evenly mixed with the soap composition of Table -4B. The soap sample for antimicrobial analysis was prepared as 8% soap slurry at 50°C and the testing was carried out at 40°C following the above mentioned method of ASTM E2783 -16 to measure the log reduction of E.coli 10536 LR after 30 seconds of contact time.

The data is summarized in Table -6 below:

Table - 6

The data in table -6 above indicates that composition as per the invention (Example -5) provides for vastly improved log reduction of E. coli bacteria as compared to the base soap noodle and a subset combination.

Examples O-R, 6: Example O-R and 6: Effect of using a different activity enhancer on the log reduction of E.coli.

Combination of actives as shown in Table -7 below were used to measure the log reduction of E.coli 10536 after one minute of contact time at 40 °C and at a pH of 9.8.

The procedure used was as described hereinabove.

The data is summarized in Table -7 below:

Table - 7

The data in table -7 above indicates that composition as per the invention (Example -6) provides for vastly improved log reduction as compared to subset combinations.

It is to be understood that the experiments described above were conducted under conditions which mimic actual washing scenario 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 generally diluted with large amounts of water.

Claims

1 . An antimicrobial cleansing composition comprising

(i) salt of lauric acid; and

(ii) at least two activity enhancers selected from amino carboxylates, polyhydroxy carboxylates, polyphosphates and dicarboximides; and

(iii) a cosmetically acceptable vehicle; wherein each of the activity enhancers is included in 0.005 to 5% by weight of the composition; and wherein at least one activity enhancer is an amino carboxylate selected from trisodium methyl glycine diacetate (MGDA) or L-glutamic acid N, N-diacetic acid tetrasodium salt (GLDA).

2. A composition as claimed in claim 1 wherein the activity enhancers are selected from trisodium methyl glycine diacetate (MGDA), L-glutamic acid N, N-diacetic acid tetrasodium salt (GLDA), sodium gluconate, hexametaphosphate (HMP), and tetra-acetyl ethylenediamine (TAED).

3. A composition as claimed in claim 1 or 2 comprising two activity enhancers.

4. A composition as claimed in any one of the preceding claims wherein the two activity enhancers are selected from the following combinations: GLDA + HMP, GLDA + sodium gluconate, GLDA + TAED, MGDA + HMP, MDGA + Na-Gluconate, MGDA + TAED, and MGDA + GLDA.

5. A composition as claimed in any one of the preceding claims comprising 0.5 to 20 wt% salt of lauric acid.

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

7. A soap bar composition as claimed in claim 6 wherein the cosmetically acceptable vehicle comprises water, soap other than salt of lauric acid, structuring agent, electrolyte, polymer or combinations thereof.

8. A soap bar composition as claimed in claim 7 wherein the soap other than salt of lauric acid is a C10-C11 soap or a C14 to C18 soap.

9. A soap bar composition as claimed in claim 7 or 8 comprising 15 to 75% soap other than salt of lauric acid, by weight of the composition.

10. A soap bar composition as claimed in any one of the preceding claims 7 to 9 comprising 14 to 40 wt% water.

11. A method of killing both gram negative and gram positive bacteria comprising the step of washing a surface with a composition as claimed in any one of the preceding claims preferably diluted with water for at least 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.