Antimicrobial composition

Abstract

The present invention relates to an antimicrobial composition that not only cleans hard and soft inanimate surfaces, but also provides antimicrobial efficacy against both gram-positive and gram-negative bacteria. This is achieved by a combination of a rhamnolipid surfactant, an amino acid surfactant and a selected chelating agent.

Description

Technical Field

[0001] This invention relates to antimicrobial compositions. More particularly, this invention relates to a composition that not only cleans both hard and soft inanimate surfaces, but also provides antimicrobial efficacy against both Gram-positive and Gram-negative bacteria. This composition is particularly useful for cleaning and disinfecting hard surfaces such as those in the kitchen, for example, the surfaces of kitchen utensils, but can also be used for disinfecting fabrics. Background Technology

[0002] Disinfecting and cleaning compositions offer significant benefits to individuals because proper use typically reduces the number of bacteria and pathogens an individual is exposed to. Such compositions are used to clean and disinfect hard surfaces, such as kitchen utensils, and other areas like toilets, bathrooms, and floors in homes and public places. In addition to clothing and fabrics used in hospitals, clothing and fabrics such as bed sheets also require disinfection, especially when used by infants. Disinfection can be achieved by including conventional bleaching agents (such as hypochlorite) in such compositions, but many consumers dislike the chlorine odor produced during use. Compositions containing cationic surfactants also provide effective disinfection, but they may require high concentrations. Furthermore, formulating cleaning and disinfecting compositions with the minimum amount of conventional antimicrobial agents that effectively kill both Gram-positive and Gram-negative bacteria is a truly challenging problem. This is even more difficult if the result is achieved without using any conventional antimicrobial agents, relying solely on a combination of selected conventional surfactants and other cleaning agents.

[0003] Therefore, the object of the present invention is to provide a composition that can disinfect surfaces to ensure the killing of both desired Gram-negative and Gram-positive bacteria. Summary of the Invention

[0004] The first aspect of the present invention relates to an antimicrobial composition comprising (i) 0.01 to 2.5% by weight of rhamnolipids; (ii) 0.025 to 2.5% by weight of an amino acid surfactant; and (iii) 0.005 to 2% by weight of a chelating agent selected from one or more of methylglycine diacetate (MGDA), sodium N,N-diacetate of L-glutamic acid (GLDA), sodium gluconate and octylhydroxamic acid.

[0005] Another aspect of the invention relates to a method for killing both Gram-positive and Gram-negative bacteria on a surface, comprising the step of contacting the surface with a composition of the first aspect, preferably diluted with water. Detailed Implementation

[0006] To avoid ambiguity, any feature of one aspect of the invention may be used in any other aspect of the invention. The word “comprising” is intended to mean “including”, but not necessarily “consisting of” or “made up of”. Thus, the term “comprising” means not limited to any element subsequently stated, but optionally also covers unspecified elements of primary or secondary functional importance. In other words, the listed steps or options need not be exhaustive. Whenever the words “comprising” or “having” are used, these terms mean equivalent to “comprising” as defined above. It should be noted that the examples given in the following specification are intended to illustrate the invention and are not intended to limit the invention to those examples themselves. Except as expressly stated in the embodiments or otherwise, all figures in this specification representing the amount of material or reaction conditions, the physical properties of the material, and / or uses should be understood to be modified by the word “about”. Unless otherwise stated, numerical ranges expressed in the format “x to y” should be understood to include both x and y. When multiple preferred ranges are described in the form of “x to y” for a particular feature, it should be understood that all ranges combining different endpoints are also considered. Unless otherwise stated, the amounts used herein are expressed as a weight percentage based on the total weight of the composition and are abbreviated as "weight%".

[0007] The compositions of this invention comprise two main surfactants: a rhamnolipid surfactant and an amino acid surfactant. Both surfactants are anionic.

[0008] The compositions of the present invention comprise rhamnolipids. Rhamnolipids are a class of glycolipids. They are constructed from rhamnose combined with β-hydroxy fatty acids. Rhamnose is a sugar. Fatty acids are ubiquitous in animals and plants.

[0009] Rhamnolipids are discussed in E. Deziel et al., Applied Microbiology and Biotechnology (2010) 86:1323-1336. Rhamnolipids are produced by Glycosurf, AGAE Technologies, and Urumqi Unite Bio-Technology Co., Ltd. Rhamnolipids can be produced by the bacteria *Pseudomonas aeruginosa* (…). Pseudomonas Aeruginosa Rhamnolipids are produced by strains of *Pseudomonas putida*. Pseudomonas Putida The recombinant cells are produced, wherein the recombinant cells contain increased activity of at least one of the enzymes a / P hydrolase, rhamnosyltransferase I, or rhamnosyltransferase II compared to wild-type cells.

[0010] There are two main groups of rhamnolipides: monorhamnolipides and dirhamnolipides. Monorhamnolipides have a single rhamnosine ring. A typical monorhamnolipide produced by *Pseudomonas aeruginosa* is L-rhamnosyl-β-hydroxydecyl-β-hydroxydecanoate (RhaC). 10 C 10 It can be called Rha-C. 10 -C 10 , having formula C 26 H 48 O9. Monorhamnolipids possess a monorhamnosyl ring.

[0011] The IUPAC name is 3-[3-[(2R,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxane-2-yl]oxydecanoyloxy]decanoic acid.

[0012] Dirhamnolipids have two rhamnosine rings. A typical dirhamnolipid is L-rhamnosyl-L-rhamnosyl-β-hydroxydecanoyl-β-hydroxydecanoate (Rha2C). 10 C 10 It can be called Rha-Rha-C. 10 -C 10 , having formula C 32 H 58 O 13 .

[0013] The IUPAC name is 3-[3-[4,5-dihydroxy-6-methyl-3-(3,4,5-trihydroxy-6-methyloxane-2-yl)oxyoxane-2-yl]oxydecanoyloxy]decanoic acid.

[0014] In practice, depending on the carbon source and bacterial strain, a variety of other minor components with different combinations of alkyl chain lengths exist alongside the more common rhamnolipide combinations described above. The ratio of monorhamnolipide to dirhamnolipide can be controlled by the production method. Some bacteria produce only monorhamnolipide (see US5767090: Example 1), and some enzymes can convert monorhamnolipide to dirhamnolipide.

[0015] In various publications, monorhamnolipids are designated by the symbol Rha-, which can be abbreviated as Rh or RL2. Similarly, dirhamnolipids are designated by the symbols Rha-Rha or Rh-Rh or RL1. Due to historical reasons, "rhamnolipid 2" is a monorhamnolipid, and "rhamnolipid 1" is a dirhamnolipid. This has led to some ambiguity in the use of "RL1" and "RL2" in the literature.

[0016] Throughout this patent specification, we use the terms monorhamnolipid and dirhamnolipid to avoid such potential confusion. However, if the abbreviations are used, R1 is monorhamnolipid and R2 is dirhamnolipid. For more information on the confusion of terminology in the prior art, see the introduction to US 4814272.

[0017] The following rhamnolipids produced by the following bacteria have been detected: (C12:1, C14:1 represent fatty acyl chains with double bonds).

[0018] Rhamnolipids (monorhamnetin) produced by Pseudomonas aeruginosa: Rha-C8-C10, Rha-C10-C8, Rha-C10-C10, Rha-C10-C12, Rha-C10-C12:1, Rha-C12-C10, Rha-C12:1-C10 Rhamnolipids (dirhamnolipids) produced by Pseudomonas aeruginosa: Rha-Rha-C8-C10, Rha-Rha-C8-C12:1, Rha-Rha-C10-C8, Rha-Rha-C10-C10, RhA-RhA-C10 -C12:1, RhA-RhA-C10-C12, RhA-RhA-C12-C10, RhA-RhA-C12:1-C12, Rha-Rha-C10-C14:1 Rhamnolipids produced by Pseudomonas aeruginosa (not identified as monorhamnolipids or dirhamnolipids): C8-C8, C8-C10, C10-C8, C8-C12:1, C12:1-C8, C10-C10, C12-C10, C12:1-C10, C12-C12, C12:1-C12, C14-C10, C14:1-C10, C14-C14.

[0019] By Pseudomonas aeruginosa ( P. chlororaphis The rhamnolipin produced (monorhamnolipin only): Rha-C10-C8, Rha-C10-C10, Rha-C12-C10, Rha-C12:1-C10, Rha-C12-C12, Rha-C12:1-C12, Rha-C14-C10, Rha-C14:1-C10.

[0020] Burkholderia nasalis (Berkholderia nasalis) Burkholdera pseudomallei The rhamnolipin produced (only dirhamnolipin): Rha-Rha-C14-C14.

[0021] Burkholderia plantarum ( Burkholdera plantarii (Pseudomonas plantarum) Pseudomonas plantarii The rhamnolipin produced (only dirhamnolipin): Rha-Rha-C14-C14.

[0022] The American Type Culture Collection (ATCC) holds over 100 archived *Pseudomonas aeruginosa* strains. Many other strains are only available to manufacturers of commercial rhamnolipin. Furthermore, thousands of strains may have been isolated by various research institutions worldwide. Some work has progressed to typing them into different groups. Each strain possesses distinct characteristics, including the amount of rhamnolipin it produces, the types of rhamnolipin it produces, what it metabolizes, and its growth conditions. Only a small percentage of strains have been studied in depth.

[0023] Through evaluation and selection, *Pseudomonas aeruginosa* strains that produce rhamnolipids at higher concentrations and more efficiently can be isolated. Strains can also be selected to produce fewer byproducts and metabolize different feedstocks or contaminants. This production is greatly influenced by the environment in which the bacteria grow.

[0024] A typical dirhamnolipid is L-rhamnosyl-L-rhamnosyl-β-hydroxydecyl-β-hydroxydecanoate (Rha2C) 10 C 10 , having formula C 32 H 58 O 13 ).

[0025] In practice, depending on the carbon source and bacterial strain, various other minor components with different combinations of alkyl chain lengths exist alongside the more common rhamnolipide combinations described above. The ratio of monorhamnolipide to dirhamnolipide can be controlled by the production method. Some bacteria produce only monorhamnolipide (see US6767090: Example 1), and some enzymes can convert monorhamnolipide to dirhamnolipide.

[0026] Preferably, the rhamnose glycolipid is selected from: - Rhamnolipids (monorhamnetin) produced by Pseudomonas aeruginosa: Rha-C8-C10, Rha-C10-C8, Rha-C10-C10, Rha-C10-C12, Rha-C10-C12:1, Rha-C12-C10, Rha-C12:1-C10 - Rhamnolipids produced by *Pseudomonas aeruginosa* (monorhamnetin only): Rha-C10-C8, Rha-C10-C10, Rha-C12-C10, Rha-C12:1-C10, Rha-C12-C12, Rha-C12:1-C12, Rha-C14-C10, Rha-C14:1-C10.

[0027] - Monorhamnolipids can also be produced from *Pseudomonas putida* by introducing the genes rhlA and rhlB from *Pseudomonas aeruginosa* [Cha et al., Bioresour Technol. 2008. 99(7):2192-9] - Rhamnolipids (dirhamnolipids) produced by Pseudomonas aeruginosa: Rha-Rha-C8-C10, Rha-Rha-C8-C12:1, Rha-Rha-C10-C8, Rha-Rha-C10-C10, Rha-Rha-C10 -C12:1, Rha-Rha-C10-C12, Rha-Rha-C12-C10, Rha-Rha-C12:1-C12, Rha-Rha-C10-C14:1 - Rhamnolipids produced by Burkholderia melioides (dirhamnolipids only): Rha-Rha-C14-C14.

[0028] - Rhamnolipids (dirhamnolipids only) produced by Burkholderia phytoholdanum (a plant pseudomonad): Rha-Rha-C14-C14 Rhamnolipids produced by Pseudomonas aeruginosa were initially not identified as monorhamnolipids or dirhamnolipids. C8-C8, C8-C10, C10-C8, C8-C12:1, C12:1-C8, C10-C10, C12-C10, C12:1-C10, C12-C12, C12:1-C12, C14-C10, C14:1-C10, C14-C14.

[0029] Preferably, the rhamnolipid is L-rhamnosyl-(3-hydroxydecanoyl-β-hydroxydecanoate) (RhaC 10 C 10 , having formula C 26 H 48 O9).

[0030] Preferably, the rhamnose glycolipid contains at least 50% by weight of dirhamnose glycolipid, more preferably at least 60% by weight of dirhamnose glycolipid, even more preferably 70% by weight of dirhamnose glycolipid, and most preferably at least 80% by weight of dirhamnose glycolipid.

[0031] Preferably, the rhamnose glycolipid is a dirhamnose glycolipid of the following formula: Rha2C 8-12 C 8-12 The preferred alkyl chain length is C8 to C9. 12 The alkyl chain can be saturated or unsaturated. The most preferred dirhamnolipid is an example of a dirhamnolipid with the following formula: Rha2C 8-12C 8-12 This is referred to herein as rhamnolipin R2, and may be supplied by Evonik. The composition comprises 0.01 to 2.5%, preferably 0.1 to 2%, more preferably 0.25 to 1.5% by weight of the composition of rhamnolipin.

[0032] Amino acid surfactants are included in the compositions of this invention. They are surfactants produced using amino acids and (vegetable) oils or fats through biotechnological and chemical methods. Because amino acids and vegetable oils or fats are renewable sources, these types of amino acid surfactants are suitable materials for detergent compositions made from renewable sources. The combination of polar amino acids and non-polar oil or fat chains provides molecules with high surface activity. Due to the wide diversity of amino acid (and peptide) structures and the diversity of chain lengths of oily or fatty groups, the properties of amino acid surfactants also vary, thus allowing specific amino acid surfactants to be used for specific purposes.

[0033] In this invention, the amino acid surfactant is preferably selected from one or more of glutamate, sarcosine, glycine, and alanine, more preferably from one or two of glutamate and sarcosine. The fatty acid chain is preferably a C6-C16 fatty acid chain, more preferably C10-C16, and most preferably a lauroyl or cocoyl chain. The amino acid is preferably selected from disodium lauroyl glutamate, disodium cocoyl glutamate, and sodium lauroyl sarcosinate.

[0034] Because oil or fatty acid chains are typically derived from natural sources, the fatty acids and alcohols they produce are not always pure, single-chain-length components. Cx-Cy generally refers to at least 50% of the alkyl chain containing x to y carbon atoms, preferably at least 60%, more preferably at least 70%, even more preferably at least 80%, even more preferably at least 90%, even more preferably at least 95%, or even at least 98%, or ideally at least 99% of the alkyl chain containing x to y carbon atoms.

[0035] The amino acid surfactant is present in the composition at a concentration of 0.025% to 2.5% based on the total weight of the composition. Preferably, the amino acid surfactant is present at a concentration of at least 0.05% by weight, more preferably at least 0.1% by weight, even more preferably at least 0.25% by weight, but preferably not more than 2.0% by weight, and more preferably not more than 1.5% by weight, based on the total weight of the composition.

[0036] The compositions of the present invention comprise one or more chelating agents selected from methylglycine diacetate (MGDA), sodium N,N-diacetate of L-glutamic acid (GLDA), sodium gluconate, and capryloyl hydroxamic acid (CHA). GLDA herein refers to the sodium salt of N,N-diacetate of L-glutamic acid. Preferred chelating agents are one or more selected from MGDA, CHA, and sodium gluconate. The composition comprises 0.005 to 2.0%, preferably 0.01 to 1.5%, and more preferably 0.05 to 1.5% of the chelating agent by weight of the composition.

[0037] Unwilling to be bound by theory, the inventors believe that the combination of rhamnolipids, amino acid surfactants, and chelating agents works by affecting the permeation of the active substances through the cell membrane of microorganisms, and then affecting the metabolism of the cells.

[0038] The compositions of the present invention preferably contain a secondary surfactant that helps to thoroughly clean surfaces. A secondary surfactant is a surfactant included in the compositions of the present invention that is different from the primary surfactant (i.e., rhamnolipid surfactants and amino acid surfactants). The secondary surfactant can be anionic, nonionic, amphoteric, or zwitterionic. For clarity, anionic secondary surfactants are referred to herein as secondary anionic surfactants.

[0039] Dishwashing Composition The compositions of this invention can be used to maintain kitchen items, such as utensils and tableware that can be cleaned using a dishwashing composition (preferably in liquid form). Various components other than the essential ingredients claimed in this invention are summarized below.

[0040] The dishwashing compositions according to the invention typically contain one or more minor surfactants in a total amount of 1 to 30% by weight, preferably 2 to 15% by weight. Preferred minor surfactants included in the compositions of the invention are anionic surfactants. Preferred minor anionic surfactants are organic sulfates and sulfonates having an alkyl group containing about 8 to about 22 carbon atoms, the term "alkyl" used for the alkyl moiety including a higher acyl group. Examples of such materials include alkyl sulfates, alkyl ether sulfates, alkylaryl sulfonates, α-olefin sulfonates, and mixtures thereof. The alkyl group preferably contains 10 to 18 carbon atoms and may be unsaturated. Alkyl ether sulfates may contain 1 to 10 ethylene oxide or propylene oxide units per molecule, preferably 1 to 3 ethylene oxide units per molecule. The counterions of the anionic surfactants are typically alkali metals, such as sodium or potassium; or ammonia counterions, such as monoethanolamine (MEA), diethanolamine (DEA), or triethanolamine (TEA). Mixtures of these counterions may also be used. Sodium and potassium are preferred.

[0041] The most preferred minor anionic surfactants are alkyl sulfate surfactants (PAS), such as non-ethoxylated primary and secondary alkyl sulfates with alkyl chain lengths of 10 to 18. Some alkylbenzene sulfonate types may also be included, particularly linear alkylbenzene sulfonates (LAS) with alkyl chain lengths of 10 to 18 carbon atoms.

[0042] Preferably, the dishwashing composition according to the invention may further comprise an amphoteric surfactant. Preferably, the amphoteric surfactant is selected from alkylamine oxides, alkyl betaines, alkylamidopropyl betaines, alkyl sulfobetaine (sulfobetaine), alkyl glycinates, alkyl carboxyglycinates, alkyl amphoteric acetates, alkyl amphoteric propions, alkyl amphoteric glycinates, alkylamidopropyl hydroxysulfobetaine, acyl taurate, and acyl glutamate, having an alkyl group containing about 8 to about 22 carbon atoms, the term "alkyl" used for alkyl moieties including higher acyl groups. More preferably, the amphoteric surfactant is selected from alkylamidopropyl betaines, even more preferably cocamidopropyl betaines. When included, the amphoteric surfactant may be present in an amount preferably from 0.1 to 5% by weight, more preferably from 0.1 to 4% by weight, even more preferably from 1 to 3% by weight. Mixtures of any of the above materials may also be used. A favorable combination of secondary surfactants in the form of the dishwashing composition of the invention is a combination of 1 to 25% by weight of an anionic surfactant and 0.1 to 5% by weight of an amphoteric surfactant.

[0043] Preferably, the dishwashing composition may further comprise 0.1% to 3% of a nonionic surfactant based on the total weight of the composition. Preferred types of such nonionic surfactants used in this invention include aliphatic C8 to C96 surfactants. 18 C is preferred 12 To C 15 The linear primary alcohol ethoxylate has an average of 3 to 20, more preferably 5 to 10, moles of ethylene oxide per mole of alcohol. The preferred nonionic surfactant is a C16 / 18 alcohol ethoxylate.

[0044] Liquid dishwashing compositions may preferably contain an organic acid or a salt thereof. Preferably, the organic acid or a salt thereof is selected from one or more of citric acid, succinic acid, malic acid, lactic acid, tartaric acid, hexanoic acid, cyclohexaneic acid, heptanoic acid, octanoic acid, 4-methyloctanoic acid, nonanoic acid, decanoic acid, benzoic acid, 4-methoxybenzoic acid, and mixtures thereof. Examples of organic acid salts include the corresponding salts of these organic acids, preferably formed with sodium and potassium, more preferably with sodium, such as trisodium citrate. More preferably, the organic acid or a salt thereof may further include maleic acid or a salt thereof. Even more preferably, the organic acid or a salt thereof is selected from citric acid or a salt thereof, such as trisodium citrate. Preferably, the composition does not contain silver dihydrogen citrate. When the composition contains an organic acid or a salt thereof, it is preferably included in 0.2 to 5% by weight, preferably 0.3 to 4% by weight, more preferably 0.4 to 3% by weight, even more preferably 0.5 to 3% by weight, and even more preferably 1 to 2% by weight. When the selected organic acid is citric acid, this may be in addition to citric acid selected as a chelating agent according to the invention.

[0045] When the dishwashing detergent is in liquid form, it preferably contains 5 to 99% by weight, more preferably 10 to 90% by weight, even more preferably 15 to 80% by weight, further preferably 20 to 70% by weight, even more preferably 30 to 65% by weight, still more preferably 35 to 60% by weight, still more preferably 40 to 55% by weight of water.

[0046] Preferably, the liquid dishwashing composition further comprises one or more sequestrants. Preferably, the sequestrant may be present in an amount of 0.1 to 5% by weight, more preferably 0.25 to 4% by weight, or even more preferably 0.5 to 2.5% by weight.

[0047] Preferred multivalent chelating agents are phosphonic acids or their salts. Phosphonic acid (or its salts) multivalent chelating agents are preferably selected from 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP, commercially available as Dequest® 2010), diethylenetriaminepenta (DTPMP, commercially available as Dequest® 2066), hexamethylenediaminetetra(methylenephosphonic acid) (HDTMP), aminotri(methylenephosphonic acid) (ATMP), ethylenediaminetetra(methylenephosphonic acid) (EDTMP), tetramethylenediaminetetra(methylenephosphonic acid) (TDTMP); and phosphonobutanetricarboxylic acid (PBTC). The most preferred multivalent chelating agent is 1-hydroxyethylidene-1,1-diphosphonic acid (HEDP). It is preferred that the multivalent chelating agent be added to the formulation in acid form.

[0048] Optionally, the liquid dishwashing composition further comprises an enzyme, with or without a suitable enzyme stabilizer. Preferably, the composition further comprises an effective amount of at least one enzyme, with or without a suitable enzyme stabilizer. Examples of suitable enzymes include pectic acid lyase, protease, amylase, cellulase, lipase, and mannanase; with or without a suitable stabilizer.

[0049] When in liquid form, the viscosity of the dishwashing composition at 25°C is 21 seconds. -1 Suitable shear rates range from about 200 mPa·s to about 10,000 mPa·s. This shear rate is the shear rate typically applied to the liquid when the bottle is poured. Pourable liquid home care compositions typically have a viscosity of 200 mPa·s to 1,500 mPa·s, preferably 100 mPa·s to 800 mPa·s.

[0050] The liquid dishwashing composition preferably has a pH of 2.5 to 12, more preferably 3 to 8, and most preferably 4 to 6.5.

[0051] The liquid dishwashing composition may further comprise one or more polymers. Preferably, the polymers may be cationic, anionic, amphoteric, or nonionic with a molecular weight greater than 100,000 Daltons. They are known to improve the viscosity and stability of the liquid composition, enhance the skin feel during and after use, and improve foam creaminess and foam stability. Examples of polymers include polyvinyl alcohol, polyacrylic acid, silanes, siloxanes, and mixtures thereof. If present, the polymer may preferably be present in the composition in an amount ranging from 0.001 to 10% by weight, more preferably from 0.1 to 6% by weight, and even more preferably from 1 to 3% by weight.

[0052] Preferably, the composition can be used as is, i.e., clean, or it can be diluted before use. The degree of dilution usually depends on market selection. In some markets, a more concentrated product is required, while in other markets, a more diluted product is preferred. When the composition is a liquid dishwashing composition, it is usually diluted with water at a weight ratio in the range of 1:1 to 1:20, more preferably 1:1 to 1:10.

[0053] Liquid dishwashing compositions may optionally contain ingredients such as fragrances, colorants, foam promoters, and odor-absorbing materials.

[0054] Laundry detergent composition : The composition can be provided as a laundry detergent composition, which, in addition to the basic components of the present invention, may contain 1 to 80% by weight, preferably 2 to 60% by weight, and more preferably 4 to 30% by weight, of a secondary surfactant. The secondary surfactant is preferably anionic, nonionic, or a mixture thereof. The secondary anionic surfactants that may be included are listed in the above section on dishwashing compositions. The nonionic surfactants that may be included are also listed in the above section on dishwashing compositions. The laundry detergent composition may be delivered in solid form or as a liquid.

[0055] The laundry detergent compositions that can be delivered in this invention are preferably in liquid form. The term liquid can encompass emulsions, suspensions, and compositions having a flowable but firmer consistency, referred to as gels or pastes. Pourable liquid detergent compositions preferably have a viscosity of 200 to 1,500 mPa·s, more preferably 200 to 700 mPa·s. Such compositions typically have an aqueous continuous phase. Preferably, the composition contains at least 50% by weight of water, more preferably at least 70% by weight of water. Water is typically present in an amount of 20% to 99.9% by weight of the composition, preferably 40% to 80% by weight.

[0056] In addition to the ingredients mentioned above, liquid laundry detergent compositions typically contain agents such as stain-removing polymers, water-soluble solvents, surfactants, builders, polymer thickeners, and color-correcting dyes. Stain-removing polymers (SRPs) help improve the removal of dirt from fabrics by altering the fabric surface during washing.

[0057] The SRP structure may also include end-capping groups to control molecular weight or modify polymer properties, such as surface activity. Preferred SRPs for use in this invention comprise copolyesters formed by the condensation of terephthalate and glycol (preferably 1,2-propylene glycol), and further comprise end caps formed from alkyl-terminated epoxy repeating units. When included, the SRP can range from 0.1 to 10% by weight of the composition, ideally 0.3 to 7% by weight, more preferably 0.5 to 5% by weight.

[0058] The compositions of the present invention may incorporate non-aqueous carriers, such as co-solvents, co-solvents, and phase stabilizers.

[0059] Liquid laundry detergent compositions may optionally contain relatively low levels of organic detergent builders or polyvalent chelating agents. Examples include alkali metal citrates, succinates, malonates, carboxymethyl succinates, carboxylates, polycarboxylates, aminocarboxylates, and polyacetylcarboxylates. If used, the organic builder material may comprise from about 0.5% to 20% by weight of the composition, preferably from 1% to 10% by weight.

[0060] When the composition is a liquid laundry detergent composition, it can be diluted with water at a weight ratio in the range of 1:50 to 1:800, more preferably 1:100 to 1:500, to form a detergent solution.

[0061] The solid laundry composition of the present invention can be in various physical solid forms, including such forms as powder, granules, strips, thin strips, pastes, tablets, flakes, lozenges and strips, and preferably the composition is in the form of powder, granules or strips.

[0062] The compositions according to the invention can be prepared by a variety of conventional methods known in the art, including dry mixing, compaction (e.g., agglomeration, extrusion, tableting), or spray drying of various compounds contained in the detergent components, or combinations of these techniques. The powder or granular compositions preferably have a density greater than 350 g / L, more preferably greater than 450 g / L, or even greater than 570 g / L.

[0063] Typical solid laundry detergent compositions contain one or more minor surfactants selected from anionic, nonionic, amphoteric, or amphoteric types, preferably anionic. These solid compositions typically contain 1 to 30% by weight of a minor anionic surfactant. Details of the various components described for liquid detergent compositions (such as anionic and nonionic surfactants, SRPs, water-soluble solvents, builders, etc.) may also be included in the solid detergent compositions. Additionally, they may contain other auxiliaries to provide benefits to the washed fabrics, such as anti-redeposition polymers, which may be included together at 0 to 5% by weight of the composition. Builders are typically included, particularly to counteract the adverse effects of water hardness used to wash fabrics, and these comprise up to 50% by weight of the composition, typically 10 to 30% by weight. Other fabric-beneficial agents, such as color-correcting dyes and optical brighteners, may be included at up to 1% by weight of the composition. Bleach may sometimes be included, and when included, it comprises up to 10% by weight of the composition, and fillers typically comprise up to 40% by weight of the composition.

[0064] When measured at 1% by weight in deionized water at 25°C, the solid laundry detergent composition according to the invention preferably has a pH of 7.0 to 10.5, more preferably 7.0 to 10.2, and even more preferably 8.5 to 10.2. The composition may preferably contain a buffer.

[0065] Typically, it is preferred that the compositions of the present invention used for most of the above applications be in liquid form.

[0066] The present invention also relates to the elimination of both Gram-positive and Gram-negative bacteria from a surface, comprising the step of contacting the surface with a composition of the present invention, preferably diluted with water. The surface is preferably non-living. The method is preferably non-therapeutic.

[0067] The invention will now be described with the aid of the following non-limiting embodiments.

[0068] Example Example AD, 1: Effect of the composition on the logarithmic killing of Staphylococcus aureus.

[0069] Log-kill of Staphylococcus aureus at two time points (5 minutes and 10 minutes) was measured using combinations of active substances as shown in Table-1 below: The procedure used is as follows: The suspension test in this embodiment is based on the general test procedure of EN1276.

[0070] Use 10 8 The bacterial count was calculated as 1000 bacteria / ml as the bacterial culture. In this test, 8 ml of the preparation was used with 1 ml of bacterial culture and 1 ml of BSA solution. The concentration of the BSA solution was 0.03% to simulate “clean” surface conditions. After mixing the above solutions, the bacterial count was diluted 10-fold to produce the initial 10000 bacterial counts at the start of the experiment. 7 Bacterial count per ml.

[0071] The formulation and bacteria were kept in contact for appropriate time points (5 minutes and 10 minutes, as specified in the examples below), and then neutralized (to quench the efficacy of the active substance and stop its antibacterial action). The reduction in the number of bacteria passing through the formulation was calculated relative to the water control. The examples were conducted at room temperature of 23°C.

[0072] Target organism: Staphylococcus aureus ATCC 6538 (Gram-positive bacteria).

[0073] The rhamnolipid used is V10075 from Evonik, Germany.

[0074] The data is summarized in Table-1 below: Table 1

[0075] The data in Table 1 above show that the composition according to the invention (Example 1) provides a significantly enhanced improvement in logarithmic killing compared to individual components or subset combinations.

[0076] Examples EH, 2, and 3: Effect of the composition on the logarithmic killing effect of Pseudomonas aeruginosa Log-kill of *Pseudomonas aeruginosa* was measured using the combination of active substances shown in Table-2 below (at 5 and 10 minutes). *Pseudomonas aeruginosa* is a Gram-negative bacterium. The procedure used was the same as that used in Table-1 previously.

[0077] The data is summarized in Table 2 below: Table 2

[0078] The data in Table 2 above show that the compositions according to the invention (Examples 2 and 3) provide a significant improvement in logarithmic killing of Pseudomonas aeruginosa, similar to their efficacy against Staphylococcus aureus.

[0079] Examples IK, P, 4, 5: Effects of other chelating agents Log-kill of Staphylococcus aureus was measured using the combination of active substances shown in Table 3 below (at 5 and 10 minutes).

[0080] The procedure used is the same as that previously used in Table-1.

[0081] The data is summarized in Table 3 below: Table 3

[0082] The data in Table 3 above show that the compositions according to the invention (Examples 4 and 5), together with other chelating agents, also provide a synergistic improvement in logarithmic killing against Staphylococcus aureus. The use of sodium citrate (Example P) as a chelating agent in such compositions provides poor antimicrobial killing.

[0083] Examples M, N, 6: Effects of another chelating agent The combination of active substances shown in Table 4 below was used to measure the logarithmic killing effect on Staphylococcus aureus over a very short time period (30 seconds) and at a very low concentration.

[0084] The procedure used is the same as that previously used in Table-1.

[0085] The data is summarized in Table 4 below: Table 4

[0086] The data in Table 4 above show that the composition according to the invention (Example 6) together with another chelating agent provides a significant improvement in logarithmic killing of Staphylococcus aureus at a very short time and at a very low concentration.

[0087] It should be understood that the above experiments were conducted in vitro to evaluate antimicrobial properties. This assay was performed under conditions simulating cleaning action, wherein the compositions of the present invention were diluted with water to a concentration representing that used by consumers in actual use. The weight ratio of water used for dilution according to the present invention can range from 1:1 to 1:800, preferably from 1:10 to 1:500, and most preferably from 1:10 to 1:250.

Claims

1. An antimicrobial composition comprising (i) 0.01 to 2.5% by weight of rhamnolipids; (ii) 0.025 to 2.5% by weight of an amino acid surfactant; and (iii) 0.005 to 2% by weight of a chelating agent selected from one or more of methylglycine diacetate (MGDA), sodium N,N-diacetate of L-glutamic acid (GLDA), sodium gluconate and capryloyl hydroxamic acid (CHA).

2. The composition according to claim 1, wherein the amino acid surfactant is selected from one or more of glutamate, sarcosinate, glycine and alanine.

3. The composition according to claim 2, wherein the amino acid surfactant is one or both of glutamate and sarcosinate.

4. The composition according to any one of the preceding claims, wherein the chelating agent is one or more of MGDA, CHA and sodium gluconate.

5. The composition according to any one of the preceding claims is a dishwashing composition comprising 1 to 25% by weight of a minor anionic surfactant.

6. The composition according to claim 5, comprising 0.1 to 5% by weight of an amphoteric surfactant.

7. The composition according to any one of claims 1 to 4, wherein it is a laundry detergent composition comprising 1 to 80% by weight of a minor surfactant, preferably an anionic surfactant.

8. The composition according to any one of the preceding claims, wherein it is in liquid form.

9. A method for killing both Gram-positive and Gram-negative bacteria from a surface, comprising the step of contacting the surface with the composition of any one of the preceding claims, wherein the composition is preferably diluted with water.

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