DISHWASHING PRODUCTS AND METHODS TO REDUCE ODORS ON SURFACES

Abstract

This invention relates to a dishwashing preparation used to reduce odors on kitchen surfaces. Specifically, it relates to a cleaning preparation for hard kitchen surfaces such as utensils, countertops, stovetops, and soft surfaces such as sponges, cloths, and scrubbing brushes, which are tools used to clean kitchen surfaces. The invention ensures that these surfaces remain fresh and odor-free for an extended period after cleaning with this preparation. This is achieved through the combination of rhamnolipids with Bacillus bacterial spores in a dishwashing preparation containing a surfactant.

Description

[0001] A DISHWASH COMPOSITION

[0002] Field of the Invention

[0003] The present invention relates to a dishwashing composition that is used to reduce malodour on surfaces. Particularly, the present invention relates to a cleaning composition that ensures that hard surfaces in the kitchen like utensils, table tops, stoves and soft surfaces like sponges, cleaning cloth and scrubs that are implements used to clean surfaces in the kitchen, remain fresh and free of malodour for long time after the surface is cleaned with the composition.

[0004] Background of the Invention

[0005] Hard surfaces which consumers wish to keep clean in the kitchen, include utensils which may be made of steel, ceramic, glass etc. Other surfaces like table tops, stoves and other surfaces in the kitchen also need to be kept clean. Such hard surfaces in the kitchen sometimes have an unpleasant odour although they may have been cleaned well. This could be due to residues of starch, protein and oils left on them which may decay over time in the presence of residual water or by moisture condensing from humid air. In the kitchen, implements having soft surfaces like cleaning cloth, sponges and brushes / scrubs used to clean utensils also develop malodour as a consequence of the above residues decaying on them. As per the present invention ‘dishwash composition’ is meant a composition to clean one or more of the above mentioned surfaces.

[0006] Thus, in cleaning most surfaces in the kitchen whether hard surfaces or soft surfaces, there is a need to deliver sufficient cleaning and hygiene while ensuring that malodour developed over a course of time after the cleaning step, is reduced while at the same time using less harsh chemicals. The present inventors while searching for a solution to this problem hit upon a surprising combination of a bacterial spore of the Bacillus genus and a biosurfactant of the rhamnolipid class which not only cleaned the surface well but also ensured that the place smells fresh for a long time and develops minimal malodour thereafter.

[0007] Cleaning composition comprising biosurfactant are known e.g. US7556654B1 which discloses a combination of this type of surfactant with an enzyme to product the cleaning benefit. The cleaning composition is shown to be formed by action of a bacteria and a yeast to lipopeptides and sophorolipids and an enzyme derived from sea kelp. It does not disclose that a combination of a rhamnolipid and a bacterial spore of the Bacillus genus ensured that malodour is significantly reduced long after the cleaning is done. It is therefore an object of the present invention to provide for a cleaning composition for cleaning surfaces in the kitchen that provides malodour benefits for a long time after they have been cleaned.

[0008] Summary of the Invention

[0009] The first aspect of the present invention relates to a dishwash composition comprising

[0010] (i) 0.05 to 10 wt% a rhamnolipid; and

[0011] (ii) 0.000005 to 1 wt% of a Bacillus bacterial spore comprising Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus subtilis', and

[0012] (iii) 1 to 30 wt% anionic surfactant

[0013] According to another aspect of the present invention there is provided a method of reducing malodour on a surface comprising the step of contacting the surface with a composition of the invention preferably diluted with water.

[0014] Detailed Description of the Invention

[0015] For the avoidance of doubt, any feature of one aspect of the present invention may be utilised in any other aspect of the invention. The word "comprising" is intended to mean "including" but not necessarily "consisting of” or "composed of'. Thus, the term "comprising" is meant not to be limiting to any subsequently stated elements, but rather to optionally also encompass nonspecified elements of major or minor functional importance. In other words, the listed steps or options need not be exhaustive. Whenever the words "including" or "having" are used, these terms are meant to be equivalent to "comprising" as defined above. It is noted that the examples given in the description below are intended to clarify the invention and are not intended to limit the invention to those examples per se. Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and / or use are to be understood as modified by the word "about". Unless specified otherwise, numerical ranges expressed in the format "x to y" are understood to include x and y. When for a specific feature multiple preferred ranges are described in the format "x to y", it is understood that all ranges combining the different endpoints are also contemplated. Unless specified otherwise, amounts as used herein are expressed in percentage by weight based on total weight of the composition and is abbreviated as “wt%”.

[0016] By a ‘surfactant’ as per this invention is meant a surfactant other than the rhamnolipid claimed in the present invention. Consequently, by ‘an anionic surfactant’ is meant an anionic surfactant other then the rhamnolipid claimed in the present invention. The composition of the invention comprises a rhamnolipid. Rhamnolipids are a class of glycolipid. They are constructed of rhamnose combined with beta-hydroxy fatty acids. Rhamnose is a sugar. Fatty acids are ubiquitous in animals and plants.

[0017] Rhamnolipids are discussed in Applied Microbiology and Biotechnology (2010) 86:1323- 1336 by E. Deziel et al. Rhamnolipids are produced by Glycosurf, AGAE Technologies and Urumqi Unite Bio-Technology Co., Ltd. Rhamnolipids may be produced by strains of the bacteria Pseudomonas Aeruginosa. Rhamnolipids may also be produced by a recombinant cell of Pseudomonas Putida where the recombinant cell comprises increased activity of at least one of the enzymes a / P hydrolase, rhamnosyltransferase I or rhamnosyl-transferase II compared to the wild-type of the cell.

[0018] There are two major groups of rhamnolipids; mono-rhamnolipids and di-rhamnolipids. Monorhamnolipids have a single rhamnose sugar ring. A typical mono-rhamnolipid produced by P. aeruginosa is L-rhamnosyl-p-hydroxydecanoyl-p-hydroxydecanoate (RhaCwCw). It may be referred to as Rha-Cw-Cw, with a formula of C26H48O9. Monorhamnolipids have a single rhamnose sugar ring.

[0019] The IUPAC Name is 3-[3-[(2R,3R,4R,5R,6S)-3,4,5-trihydroxy-6-methyloxan-2- yl]oxydecanoyloxy]decanoic acid.

[0020] Di-rhamnolipids have two rhamnose sugar rings. A typical di-rhamnolipid is L-rhamnosyl-L- rhamnosyl-p-hydroxydecanoyl-p-hydroxydecanoate (Rha2C Cio). It may be referred to as Rha- Rha-C- -C-10, with a formula of C32H58O13.

[0021] The IUPAC name is 3-[3-[4,5-dihydroxy-6-methyl-3-(3,4, 5-tri hydroxy-6-methyloxan-2- yl)oxyoxan-2-yl]oxydecanoyloxy]decanoic acid.

[0022] In practice, a variety of other minor components with different alkyl chain length combinations, depending upon carbon source and bacterial strain, exist in combination with the above more common rhamnolipids. The ratio of mono-rhamnolipid and di-rhamnolipid may be controlled by the production method. Some bacteria only produce monorhamnolipid, see US5767090: Example 1 , some enzymes can convert mono-rhamnolipid to di-rhamnolipid. In various publications mono-rhamnolipids have the notation Rha-, which may be abbreviated as Rh or RL2. Similarly, di-rhamnolipids have the notation Rha-Rha or Rh-Rh or RL1. For historical reasons "rhamnolipid 2" is a mono-rhamnolipid and "rhamnolipid 1 "is a di-rhamnolipid. This leads to some ambiguity in the usage or "RL1 " and "RL2" in the literature.

[0023] Throughout this patent specification, we use the terms mono- and di-rhamnolipid in order to avoid this possible confusion. However, if abbreviations are used R1 is mono-rhamnolipid and R2 is di- rhamnolipid. For more information on the confusion of terminology in the prior art, see the introduction to US 4814272.

[0024] The following rhamnolipids have been detected as produced by the following bacteria: (C12:1 , C14:1 indicates fatty acyl chains with double bonds).

[0025] Rhamnolipids produced by P. aeruginosa (mono-rhamnolipids):

[0026] Rha-C8-C10, Rha-C10-C8, Rha-C10-C10, Rha-C10-C12, Rha-C10-C12:1 , Rha-C12-C10, Rha- C12:1-C10

[0027] Rhamnolipids produced by P. aeruginosa (di-rhamnolipids):

[0028] Rha-Rha-C8-C10, Rha-Rha-C8-C12:1 , Rha-Rha-C10-C8, Rha-Rha-C10-C10, Rha-Rha-C10- C12:1 , Rha-Rha-C-10-C-12, Rha-Rha-C-12-C-10, Rha-Rha-C-12:1-C-12, Rha-Rha-C10-C14:1

[0029] Rhamnolipids produced by P. aeruginosa (unidentified as either mono- or di-rhamnolipids): 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.

[0030] Rhamnolipids produced by P. chlororaphis (mono-rhamnolipids only):

[0031] Rha-C10-C8, Rha-C10-C10, Rha-C12-C10, Rha-C12:1-C10, Rha-C12-C12, Rha-C12:1- C12, Rha-C14-C10. Rha-C- 14:1-010.

[0032] Rhamnolipids produced by Burkholdera pseudomallei (di-rhamnolipids only): Rha-Rha-C14-C14.

[0033] Rhamnolipids produced by Burkholdera (Pseudomonas) plantarii (di-rhamnolipids only): Rha-Rha-C14-C14. There are over 100 strains of P. aeruginosa on file at the American Type Culture Collection (ATCC). There are also a number of strains that are only available to manufacturers of commercial Rhamnolipids. Additionally, there are probably thousands of strains isolated by various research institutions around the world. Some work has gone into typing them into groups. Each strain has different characteristics including how much rhamnolipid is produced, which types of rhamnolipids are produced, what it metabolizes, and conditions in which it grows. Only a small percentage of the strains have been extensively studied.

[0034] Through evaluation and selection, strains of P. aeruginosa can be isolated to produce rhamnolipids at higher concentrations and more efficiently. Strains can also be selected to produce less byproduct and to metabolize different feedstock or pollutants. This production is greatly affected by the environment in which the bacterium is grown.

[0035] A typical di-rhamnolipid is L-rhamnosyl-L-rhamnosyl-p-hydroxydecanoyl-p-hydroxydecanoate (Rha2CioC with a formula of C32H58O13).

[0036] In practice a variety of other minor components with different alkyl chain length combinations, depending upon carbon source and bacterial strain, exist in combination with the above more common rhamnolipids. The ratio of mono-rhamnolipid and di-rhamnolipid may be controlled by the production method. Some bacteria only produce monorhamnolipid, see US6767090: Example 1 , some enzymes can convert mono-rhamnolipid to di-rhamnolipid.

[0037] Preferably the rhamnolipid is selected from:

[0038] Rhamnolipids produced by P. aeruginosa (mono-rhamnolipids):

[0039] Rha-C8-C10, Rha-C10-C8, Rha-C10-C10, Rha-C10-C12, Rha-C10-C12:1 , Rha-C12-C10, Rha- C12:1-C10

[0040] Rhamnolipids produced by P. chlororaphis (mono-rhamnolipids only):

[0041] 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.

[0042] Mono-rhamnolipids may also be produced from P.putida by introduction of genes rhIA and rhIB from Psuedomonas aeruginosa [Cha et al. in Bioresour Technol. 2008. 99(7):2192-9]

[0043] Rhamnolipids produced by P. aeruginosa (di-rhamnolipids): Rha-Rha-C8-C10, Rha-Rha-C8-C12:1 , Rha-Rha-C10-C8, Rha-Rha-C10-C10, Rha-RhaC10- C12:1 , Rha-Rha-C10-C12, Rha-Rha-C12-C10, Rha-Rha-C12:1-C12, Rha-Rha-C10- C14:1 Rhamnolipids produced by Burkholdera pseudomallei (di-rhamnolipids only):

[0044] Rha-Rha-C14-C14.

[0045] Rhamnolipids produced by Burkholdera (Pseudomonas) plantarii (di-rhamnolipids only):

[0046] Rha-Rha-C14-C14.

[0047] Rhamnolipids produced by P. aeruginosa which are initially unidentified as either mono- or di-rhamnolipids:

[0048] 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.

[0049] Preferably the Rhamnolipid is L-rhamnosyl-(3-hydroxydecanoyl-p-hydroxydecanoate (RhaC Cio with a formula of C26H48O9).

[0050] Preferably, the rhamnolipid comprises at least 50 wt.% di-rhamnolipid, more preferably at least 60 wt.% di-rhamnolipid, even more preferably 70 wt.% di-rhamnolipid, most preferably at least 80 wt.% di-rhamnolipid.

[0051] Preferably the rhamnolipid is a di-rhamnolipid of formula: Rha2C8-i2Cs-i2. The preferred alkyl chain length is from Cs to C12. The alkyl chain may be saturated or unsaturated. The most preferred di-rhamnolipid is an example of a di-rhamnolipid of formula: Rha2C8-i2Cs-i2, known as Rhamnolipid R2 herein, and can be supplied from Evonik. The composition comprises rhamnolipid in 0.05 to 10%, preferably 0.1 to 5%, more preferably 0.5 to 3% by weight of the composition.

[0052] The composition of the invention comprises 0.000005 to 1 wt% of a Bacillus bacterial spore comprising Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus subtilis. / X preferred aspect relates to a composition comprising a combination of bacterial spores of Bacillus amyloliquefaciens, Bacillus megaterium, Bacillus pumilus and Bacillus subtilis. By a combination of bacterial spores, as per this invention, is meant that the spores of the bacteria may be included in the composition.

[0053] Yet another preferred aspect relates to a composition which additionally comprises one or both of Bacillus licheniformis, and Bacillus thuringiensis. An especially preferred aspect of the present invention relates to a combination of bacterial spores which comprises Bacillus amyloliquefaciens, Bacillus megaterium, Bacillus subtilis, Bacillus pumilus and Bacillus thuringiensis.

[0054] It is preferred that each of the bacterial spores are present in 1 to 70%, more preferably in 5 to 40% of the total number of the the bacterial spores. An even more preferred aspect of the invention relates to the bacterial spores Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus subtilis being included in 5 to 40% of the total number of the bacterial spores. An especially preferred aspect of the invention relates to the bacterial spores Bacillus pumilus and Bacillus thuringiensis each being included in 1 to 30%, preferably 5 to 20%, most preferably 5 to 15% of the total number of the bacterial spores.

[0055] The bacterial spore is included 0.000005 to 1%, preferably 0.00005 to 0.75%, further more preferably 0.0001 to 0.5% by weight of the composition. The bacterial spores for inclusion in the composition of the invention can be in powder form having a count of around 1011cfu / g, but there could be other methods of growing and introducing the spores in the composition which are well known to a person skilled in the art. Thus, in the composition, the bacterial spore is preferably included in 103to 1011cfu / g, more preferably 104to 109cfu / g, and most preferably 105to 108cfu / g of the composition.

[0056] The composition of the invention is useful for upkeep of kitchen items e.g. utensils and dishes which may be cleaned using a dishwash composition, preferably in liquid form. The various ingredients other than the essential ingredients claimed in the present invention are summarized below.

[0057] The composition of the invention includes 1 to 30 wt% anionic surfactant. Preferred anionic surfactants are of the organic sulfates and sulfonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term “alkyl” being used to include the alkyl portion of higher acyl radicals. Examples of such materials include alkyl sulfates, alkyl ether sulfates, alkaryl sulfonates, alpha-olefin sulfonates and mixtures thereof. The alkyl radicals preferably contain from 10 to 18 carbon atoms and may be unsaturated. The alkyl ether sulfates may contain from one to ten ethylene oxide or propylene oxide units per molecule, and preferably contain one to three ethylene oxide units per molecule. The counterion for anionic surfactants is generally an alkali metal such as sodium or potassium; or an ammoniacal counterion such as monoethanolamine, (MEA) diethanolamine (DEA) or triethanolamine (TEA). Mixtures of such counterions may also be employed. Sodium and potassium are preferred. Most preferred surfactants are of the alkylbenzene sulfonates type, particularly linear alkylbenzene sulfonates (LAS) with an alkyl chain length of from 10 to 18 carbon atoms. Some alkyl sulfate surfactant (PAS) may be used, such as non-ethoxylated primary and secondary alkyl sulphates with an alkyl chain length of from 10 to 18.

[0058] Preferably, the composition further comprises an amphoteric surfactant. Preferably, an amphoteric surfactants is selected from include alkyl amine oxides, alkyl betaines, alkyl amidopropyl betaines, alkyl sulfobetaines (sultaines), alkyl glycinates, alkyl carboxyglycinates, alkyl amphoacetates, alkyl amphopropionates, alkylamphoglycinates, alkyl amidopropyl hydroxysultaines, acyl taurates and acyl glutamates, having alkyl radicals containing from about 8 to about 22 carbon atoms, the term “alkyl” being used to include the alkyl portion of higher acyl radicals. More preferably, an amphoteric surfactant selected from alkyl amidopropyl betaines, even more preferably cocoamidopropyl betaine. Amphoteric surfactant, when included, may be present in an amount ranging preferably from 0.1 to 5 wt%, more preferably from 0.1 to 4 wt%, even more preferably from 1 to 3 wt%. Mixtures of any of the above described materials may also be used. A good combination of surfactants for use in the present invention in the form of a dishwash composition is one having 1 to 30 wt% anionic surfactant and 0.1 to 5 wt% an amphoteric surfactant.

[0059] Preferably, the composition comprises an non-ionic surfactant. A preferred class of nonionic surfactant for use in the invention includes aliphatic Cs to Cis, more preferably C12 to C15 primary linear alcohol ethoxylates with an average of from 3 to 20, more preferably from 5 to 10 moles of ethylene oxide per mole of alcohol. Preferred non-ionic surfactants are the C16 / 18 alcohol ethoxylates. When included non-ionic surfactant is present in 0.1 to 5% by total weight of the composition.

[0060] Liquid dishwash composition may preferably comprise an organic acid or its salts . Preferably, the organic acid or its salt may further comprise citric acid, succinic acid, malic acid, lactic acid, tartaric acid, hexanoic acid, cyclohexanoic acid, heptanoic acid, octanoic acid, 4-methyl octanoic acid, nonanoic acid, decanoic acid, benzoic acid, 4-methoxy benzoic acid and mixtures thereof. Examples of salts of organic acid include corresponding salts of these organic acids that are formed preferably with sodium and potassium, more preferably with sodium, e.g. trisodium citrate. More preferably, organic acid or its salt may further comprise maleic acid or its salt. Even more preferably, the organic acid or its salt is selected from citric acid or its salt e.g. trisodium citrate. Preferably, the composition does not comprise silver dihydrogen citrate. The composition preferably comprises an organic acid or its salts from 0.2 to 5 wt%, more preferably from 0.3 to 4 wt%, further more preferably from 0.4 to 3 wt%, even more preferably from 0.5 to 3 wt%, and optimally from 1 to 2 wt%.

[0061] Liquid dishwash compositions may comprise non-aqueous carriers such as hydrotropes, cosolvents and phase stabilizers. Such materials are typically low molecular weight, water-soluble or water-miscible organic liquids such as C1 to C5 monohydric alcohols (such as ethanol and n- or i-propanol); C2 to C6 diols (such as monopropylene glycol and dipropylene glycol); C3 to C9 triols (such as glycerol); polyethylene glycols having a weight average molecular weight (Mw) ranging from about 200 to 600; C1 to C3 alkanolamines such as mono-, di- and triethanolamines; and alkyl aryl sulfonates having up to 3 carbon atoms in the lower alkyl group (such as the sodium and potassium xylene, toluene, ethylbenzene and isopropyl benzene (cumene) sulfonates). Nonaqueous carriers, when included, may be present in an amount ranging from 0.1 to 3%, preferably from 0.5 to 1% by weight of the composition. The preferred hydrotropes are monopropylene glycol and glycerol.

[0062] Preferably, the liquid dishwash composition further comprises water in an amount ranging from 5 to 99 wt%, more preferably from 10 to 90 wt%, even more preferably from 15 to 80 wt%, further more preferably from 20 to 70 wt%, still more preferably from 30 to 65 wt%, yet more preferably from 35 to 60 wt%, yet further more preferably from 40 to 55 wt%.

[0063] Preferably, the liquid dishwash composition further comprises one or more sequestrants. Preferably, the sequestrant may be present in an amount from 0.1 to 5 wt%, more preferably from 0.25 to 4 wt%, even more preferably from 0.5 to 2.5 wt%.

[0064] A preferred sequestrant is a phosphonic acid or a salt thereof. The phosphonic acid (or salt thereof) sequestrant is preferably selected from the group consisting of 1 -Hydroxyethylidene-1 ,1 -diphosphonic acid (HEDP; commercially available as Dequest(R) 2010), Diethylenetriaminepenta(methylenephosphonic acid) (DTPMP; commercially available as Dequest(R) 2066), Hexa methylene diamine tetra(methylenephosphonic acid) (HDTMP), Amino tris(methylenephosphonic acid) (ATMP), Ethylene diamine tetra(methylenephosphonic acid) (EDTMP), Tetra methylene diamine tetra(methylenephosphonic acid) (TDTMP); and Phosphono butane tricarboxylic acid (PBTC). The most preferred sequestrant is 1 -Hydroxyethylidene-1 ,1 - diphosphonic acid (HEDP). It is preferable that the sequestrant is added to the formulation in acid form. Optionally, liquid dishwash 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 pectate lyase, protease, amylase, cellulase, lipase, mannanase; with or without an appropriate stabilizing agent. An alternate and preferred aspect relates to a dishwash composition substantially free of an enzyme.

[0065] Preferably, viscosity of the composition may suitably range from about 200 to about 10,000 mPa.s at 25°C at a shear rate of 21 sec1. This shear rate is the shear rate that is usually exerted on the liquid when poured from a bottle. Pourable liquid home care compositions generally have a viscosity of from 200 to 1 ,500 mPa.s, preferably from 100 to 800 mPa.s.

[0066] The liquid dishwash composition preferably has pH in the range from 2.0 to 8.0, preferably from 2.5 to 7.5, more preferably from 3.0 to 7.0, even more preferably from 3.5 to 7.0, further more preferably from 4.0 to 7.5, still more preferably from 4.5 to 7.5, yet more preferably from 5.0 to 7.5, still further more preferably from 5.5 to 7.5 and yet further more preferably from 6.0 to 6.5.

[0067] The liquid dishwash composition may further comprise one or more polymers. Preferably, polymers can be cationic, anionic, amphoteric or nonionic types with molecular weights higher than 100,000 Dalton. They are known to increase the viscosity and stability of liquid compositions, to enhance in-use and after-use skin sensory feels, and to enhance lather creaminess and lather stability. Examples of polymers include polyvinyl alcohol, polyacrylic acid, silane, siloxane and mixtures thereof. If present, polymers may be present in the composition in an amount ranging preferably from 0.001 to 10 wt%, more preferably from 0.1 to 6 wt%, still further more preferably from 1 to 3 wt%.

[0068] Preferably, the composition may be used as is, i.e. neat, or it may be diluted before use. The extent of dilution is generally dependent on market choice. In some markets a more concentrated product is desired while in others a more dilute product is preferred. When the composition is a liquid dishwash compositions it is typically diluted with water in a weight ratio in the range of 1 :1 to 1 :10.

[0069] The liquid dishwash composition may optionally comprise ingredients, such as fragrance, colorant, foam boosting agents, and odor absorbing materials. According to another aspect of the present invention there is provided method of reducing malodour on a surface comprising the step of contacting the surface with a composition of the invention preferably diluted with water.

[0070] The invention will now be illustrated with the help of the following non-limiting examples.

[0071] Rhamnolipid used in the experiments below was obtained as ZZDL-RHEANCE from Evonik Industries, Germany.

[0072] Examples A-F, 1-5: Effect of combination of bacterial spores and rhamnolipid on reduction of kitchen malodour measured with a sniff test.

[0073] The samples as shown in Table- 1 were taken and the malodour generated was measured using the following protocol.

[0074] Kitchen Malodour assay:

[0075] • Desized Kitchen cloth- 5 x 5 cm was used for the experiments.

[0076] • The cloth was added with 1 ml of milk & rice starch water (milk + 5% starch 1:1)

[0077] • The cloth was challenged with Acinetobacter baumanii and Moraxella osloensis (108cfu / ml)

[0078] • The formulation was added to the kitchen clothes. Control cloth was also maintained without any formulation.

[0079] • The cups was incubated at 37°C for 48 h. The malodour was scored through trained panel.

[0080] Malodour detection by sniff test

[0081] Malodour was measured on a scale from 0 (No kitchen malodour) and 5 (strong kitchen malodour). The untreated control has the maximum malodour. The odour scores were given by five expert panellists in a blinded test.

[0082] The bacterial spores in the table below were included at 1 ml at a concentration of 105cfu / ml. Table - 1 :

[0083] In the table above the following abbreviations are used for the various bacterial spores:

[0084] Ba: Bacillus amyloliquefaciens

[0085] Bm: Bacillus megaterium

[0086] Bs: Bacillus subtilis

[0087] Bl: Bacillus licheniformis

[0088] Bp: Bacillus pumilus

[0089] Bt: Bacillus thuringiensis

[0090] Refers to the spores included in the following amounts: Ba, Bm, and Bs at 5 to 40%, and Bp and Bt at 5 to 15% of the total number of the bacterial spores included.

[0091] The data in the table above indicates that the combination of various bacterial spores of the Bacillus genus and a rhamnolipid provides for synergistic interaction in reducing kitchen malodour.

[0092] Example G-K and 6-9: Effect of combination of bacterial spores (at three different concentrations) and rhamnolipid (at two different concentrations) on reduction of kitchen malodour measured with a sniff test. The samples as shown in Table-2 were taken and the malodour generated was measured using the Kitchen Malodour assay as described earlier for examples A-F and 1-5 above.

[0093] The combination of bacterial spores ( indicated as “probiotic”) in the table below was Ba + Bm + Bs + Bp + Bt at the following concentration: Ba, Bm, and Bs at 5 to 40%, and Bp and Bt at 5 to 15% of the total number of the bacterial spores included.

[0094] Table - 2 The data in the table above indicates that the invention is effective over a combination of bacterial spores and rhamnolipid each at various concentrations for reducing kitchen malodour.

Claims

Claims1. A dishwash composition comprising(i) 0.05 to 10 wt% a rhamnolipid; and(ii) 0.000005 to 1 wt% of a Bacillus bacterial spore comprising Bacillus amyloliquefaciens, Bacillus megaterium, and Bacillus subtilis', and(iii) 1 to 30 wt% anionic surfactant.

2. A composition as claimed in claim 1 additionally comprising Bacillus pumilus.

3. A composition as claimed in claims 1 or 2 additionally comprising one or both of Bacillus licheniformis and Bacillus thuringiensis.

4. A composition as claimed in any one of the preceding claims additionally comprising 0.1 to 5 wt% an amphoteric surfactant.

5. A method of reducing malodour on a surface comprising the step of contacting the surface with a composition as claimed in any one of the preceding claims preferably diluted with water.