WO2020144522A1

WO2020144522A1 - Antimicrobial composition, method of preparation, disinfectant, detergent and sanitizer containing the same and use thereof

Info

Publication number: WO2020144522A1
Application number: PCT/IB2019/061207
Authority: WO
Inventors: Riccardo De Leo; Francesco BIGI; Andrea QUARTIERI
Original assignee: Packtin S.R.L.
Priority date: 2019-01-11
Filing date: 2019-12-20
Publication date: 2020-07-16
Also published as: IT201900000520A1

Abstract

The invention relates to a composition that has antimicrobial properties, in particular a composition that comprises ethyl lauroyl arginate hydrochloride and one or more of monoesters of fatty acids. The invention also relates to the use of said composition in decontamination of a liquid such as water, in particular, the elimination of Legionella pneumophila from an aqueous liquid. Furthermore, the invention concerns a disinfectant, a sanitizer, a detergent comprising said antimicrobial composition of the invention. Moreover, the invention relates to the use of said disinfectant or detergent or sanitizer in e.g. water tank-based air purification and in e.g. the cleaning of contaminated surfaces and the prevention of (re-)contamination of surfaces by microbes. It is part of the invention that the antimicrobial composition of the invention and the disinfectant, the sanitizer and/or the detergent of the invention have growth-inhibitory activity in particular against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and/or Legionella pneumophila.

Description

ANTIMICROBIAL COMPOSITION, METHOD OF PREPARATION, DISINFECTANT, DETERGENT AND SANITIZER CONTAINING THE SAME AND USE THEREOF

Technical Field

The invention relates to a composition that has antimicrobial properties, in particular a composition that comprises ethyl lauroyl arginate hydrochloride and one or more of monoesters of fatty acids. The invention also relates to the use of said composition in decontamination of a liquid such as water, in particular the elimination of Legionella pneumophila from an aqueous liquid. Furthermore, the invention concerns a disinfectant, a detergent and/or a sanitizer comprising said antimicrobial composition of the invention. Moreover, the invention relates to the use of said disinfectant, sanitizer or detergent in e.g. water tank-based air purification and in e.g. the cleaning of contaminated surfaces and the prevention of (re-)contamination of surfaces by microbes. It is part of the invention that the antimicrobial composition of the invention and the disinfectant, the sanitizer or the detergent of the invention have growth-inhibitory activity in particular against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and/or Legionella pneumophila.

Background Art

Surfaces of objects and articles ranging as broad as from floors, ceilings, door panels, glass panes to e.g. medical devices, implants, machinery, kitchen desks, kitchen equipment, etc., all may become contaminated or colonized by microorganisms such as moulds, fungi, bacteria, i.e. Gram positive bacteria and Gram negative bacteria, and as a matter of fact are almost always to some extent contaminated with microbes when left uncleaned. Protecting humans from suffering from health issues or even life-threatening disease by contacting such contaminated surfaces is an ongoing struggle in e.g. the field of surgery, households, food manufacturing, healthcare, child care, meat processing, schools, public transport, toilets, etc.

Commercially available disinfectants, soaps, detergents and sanitizers used to combat the contamination of solutions and surfaces with pathogens such as bacteria are only effective to some extent in reducing or preventing the microbial contamination. Unfortunately, such disinfectants commonly cause problems related to the environment and human health associated with the use of the disinfectants, soaps, detergents and sanitizers.

Common disinfectants and detergents contain compounds such as chlorine, ozone, chlorine dioxide or chloramines that react with naturally occurring organic matter, anthropogenic contaminants and other natural elements, which leads to the formation of DBPs (Disinfection By-Products). These DBPs formed can have negative or uncertain effects on the environment and on human health. Disinfection of water with common disinfectants can cause an increased risk for cancer and negative reproductive/developmental effects in human beings that come into contact with said disinfected water.

These are unacceptable risks associated with the use of these disinfectants and detergents, and so the search for alternative disinfectants and detergents is ongoing.

One alternative that has been found is disinfectants that contain quaternary ammonium compounds (QACs). QACs do not cause the formation of DBPs and are therefore safer to use in regard to human health. However, QACs are highly toxic to numerous aquatic organisms including fish, daphnids, algae, rotifer and other microorganisms employed in e.g. wastewater treatment systems. This means that frequent use of these compounds can lead to severe damage of the aquatic ecosystem. Additionally, even though QACs are considered biodegradable in aerobic conditions, QACs can accumulate in anaerobic environments. This would increase the toxicity of areas in which QACs have accumulated significantly, for example sludge from wastewater facilities. If such sludge were to be released into the environment it could pose serious risks to both aquatic and terrestrial organisms.

Even though QACs solve some of the health risk problems that are associated with DBPs, the QACs cause other unacceptable consequences associated with their frequent use.

As a consequence of the aforementioned shortcomings, the search for improved or new disinfectants, soaps, detergents and sanitizers receives continuous effort, the improved disinfectant, soaps, detergents and sanitizers or new disinfectant, soaps, detergents and sanitizers being more efficient, more efficacious and/or safer when duration of prevention from contamination is considered, and/or extent of decontamination is considered, and/or the risk for affecting human health or the environment is considered.

Description of the Invention

A first goal of the invention is to provide an antimicrobial composition with improved antimicrobial activity towards microbes such as bacteria, the antimicrobial composition suitable for use in the decontamination of an aqueous solution such as water, preferably without posing an unacceptable risk to the environment or to human health.

A second goal of the invention is to provide an improved disinfectant, soap, detergent and/or sanitizer with regard to the killing of microbes, preferably bacteria, and/or the prevention of microbial growth on a surface or in an aqueous solution, that, unlike disinfectants, soaps, detergents and sanitizers in the state of the art, wherein the disinfectant, detergent and/or sanitizer preferably does/do not contain compounds that can cause negative consequences to the environment and human health, and is still sufficiently effective in eliminating contamination.

Embodiments of the Invention

The present invention is described with respect to particular embodiments, but the invention is not limited thereto but only by the claims.

Furthermore, the terms first, second, third and the like in the description and in the claims, are used for distinguishing between similar elements or features and not necessarily for describing a sequential or chronological order. The terms are interchangeable under appropriate circumstances and the embodiments of the invention can operate in other sequences than described or illustrated herein.

The embodiments of the invention described herein can operate in combination and cooperation, unless specified otherwise.

Furthermore, the various embodiments, although referred to as“preferred” or “e.g.” or“for example” or“in particular”, are to be construed as exemplary manners in which the invention may be implemented rather than as limiting the scope of the invention. The term“comprising”, used in the claims, should not be interpreted as being restricted to the elements, features or steps listed thereafter; it does not exclude other elements, features or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression“a method comprising step A and step B” should not be limited to the method consisting only of step A and step B, rather with respect to the present invention, the only enumerated steps of the method are A and B, and further the claim should be interpreted as including equivalents of those steps.

In addition, reference to an element or a feature by the indefinite article "a" or "an" does not exclude the possibility that more than one of the elements or the feature are present, unless the context clearly requires that there is one and only one of the elements or the features. The indefinite article "a" or "an" thus usually means "at least one".

A first aspect of the invention relates to an antimicrobial composition comprising:

(a) at least one monoglycerol ester of a fatty acid; and

(b) ethyl lauroyl arginate.

The terms“monoglycerol ester of a fatty acid” and“monoglyceride” can be used interchangeably and both refer to the mono-ester of glycerol and a fatty acid.

Preferably, the monoglyceride is the monoglycerol ester of a fatty acid selected from a monoester of glycerol and butyric acid, capric acid, caprylic acid or lauric acid.

In an embodiment, the antimicrobial composition according to the invention comprises less than 0.6% by weight nitrogen based on the total weight of the antimicrobial composition and/or is free of phosphorus and/or is free of sulphur, preferably, the antimicrobial composition comprises less than 0.45% by weight nitrogen based on the total weight of the antimicrobial composition and is free of phosphorus and of sulphur.

Typically, the pH of the antimicrobial composition according to the invention is between 4 and 10, preferably about 4.55.

A second aspect of the invention relates to a disinfectant, sanitizer or detergent comprising the antimicrobial composition according to the invention and a diluent, preferably water.

It is preferred that the disinfectant, sanitizer or detergent of the invention at least has antimicrobial activity against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and Legionella pneumophila.

A third aspect of the invention relates to the use of the disinfectant of the invention in purification of air contaminated with a microbe such as a bacterium, preferably in the purification of air by water tank-based air purification.

A fourth aspect of the invention relates to the use of the disinfectant, sanitizer or detergent of the invention in decontaminating a surface contaminated with a microbe such as a bacterium and/or in preventing a surface from contamination with a microbe such as a bacterium. An example is the use of the disinfectant, the sanitizer or the detergent, wherein the surface is a surface of a body such as a human body, such as the hand of a human subject.

A fifth aspect of the invention relates to the use of the antimicrobial composition according to the invention in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, wherein the antimicrobial composition is added to the aqueous solution at a concentration of at least 0.2% by weight of the antimicrobial composition based on the total weight of the aqueous solution, preferably between 0.3% and 25% by weight, more preferably between 0.5% and 5% by weight, most preferably between 0.7% and 4% by weight, such as 0.75% by weight, 1.5% by weight and 3% by weight, based on the total weight of the aqueous solution. It is also part of the invention that the use of the antimicrobial composition according to the invention in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, encompasses the step of adding the antimicrobial to the aqueous solution to a final concentration of less than 0,2% by weight of the antimicrobial composition based on the total weight of the aqueous solution, such as 0,15%, 0,125%, 0,1%, 0,075%, 0,05% or lower, based on the total weight of the aqueous solution, such as 0,025-0,2% by weight.

Preferably, the antimicrobial composition of the invention has antimicrobial activity against at least Legionella pneumophila when the antimicrobial composition is used according to the invention.

DEFINITIONS

The term“antimicrobial activity” has its regular scientific meaning throughout the text, and here refers to activity that kills or stops the growth of microorganisms.

The term“carrier” as used herein has its regular scientific meaning throughout the text, and refers to anything in which or on which contaminants, such as microorganisms, i.e. microbes such as bacteria can be present and/or grow. Typically, such a carrier is an aqueous solution, a gas such as air, an article, or a surface such as the surface of an object such as for example the surface of a ceiling, wall, floor, table, kitchen worktop, machinery, etc.

The term“surface” has its regular scientific meaning throughout the text, and here refers to any part of an object constituting its external layer , including plan surfaces such as floors, ceilings, door panels, glass panes, kitchen desk etc. but also other objects e.g. medical devices, implants, machinery, kitchen equipment, etc. In addition, the term“surface” refers to the surface of a body such as a human body, such as the skin of the hands of a human subject.

The term“contamination” as used herein refers to the undesired presence of pathogens in or on an object or in an aqueous solution or in a gas such as air.

The term“disinfectant” has its regular scientific meaning throughout the text, and here refers to an antimicrobial agent or antimicrobial solution that is for example applied to a gas such as air, or to the surface of non-living objects, for the purpose of destroying microorganisms living on said objects or preventing contamination of said objects by microbes such as bacteria.

The term “disinfection by-product” has its regular scientific meaning throughout the text, and here refers to the compounds resulting from (chemical) reactions between organic and inorganic matter in water during the water disinfection process.

The term“ethyl lauroyl arginate hydrochloride” or“ethyl lauroyl arginate” has its regular scientific meaning throughout the text, and here refers to the substance with a broad range of antimicrobial activity and low toxicity formed from arginine and lauric acid, which are substances normally found in for example food. The IUPAC name for ethyl lauroyl arginate is“ethyl (2S)-5- (diaminomethylideneamino)-2-(dodecanoylamino)pentanoate”.

The term“monoester” has its regular scientific meaning throughout the text, and here refers to an ester of a polyhydric alcohol such as glycerol containing only a single ester group.

The term“monoglyceride” has its regular scientific meaning throughout the text, and here refers to the class of glycerides which are composed of a molecule of glycerol linked to a single fatty acid via an ester bond.

The term“quaternary ammonium compound” has its regular scientific meaning throughout the text, and here refers to the compound formed from the alkylation of tertiary amines with a halocarbon.

The term“water tank-based air purification” as used herein refers to the process of purifying air by passing incoming air through a tank filled with water containing a disinfectant and expelling the air that has passed the water and has been purified in the water.

DETAILED DESCRIPTION

A first aspect of the invention relates to an antimicrobial composition comprising at least one monoglycerol ester of a fatty acid and ethyl lauroyl arginate. Preferably, the antimicrobial composition is a liquid such as an aqueous solution, according to the invention.

In a preferred embodiment the antimicrobial composition of the invention comprises at least one monoglycerol ester of a fatty acid, wherein the monoglycerol ester of a fatty acid is/are selected from a monoester of glycerol and butyric acid, a monoester of glycerol and capric acid, a monoester of glycerol and caprylic acid or a monoester of glycerol and lauric acid. Here, the 1- monoesters and 2- monoesters are at isomeric equilibrium, and at room temperature the equilibrium between the two esters is strongly in favour of 1- monoglycerides, that constitute therefore the great majority of the monoglycerol ester (about 95%). Preferably, the antimicrobial composition of the invention comprises two, three, four or five monoglycerol esters of a fatty acid, such as two or three or four of a monoester of glycerol and butyric acid, a monoester of glycerol and capric acid, a monoester of glycerol and caprylic acid or a monoester of glycerol and lauric acid. It is preferred that the antimicrobial composition of the invention comprises at least one monoglycerol ester of a fatty acid, wherein the monoglycerol ester of a fatty acid comprises a monoester of glycerol and butyric acid, a monoester of glycerol and capric acid, a monoester of glycerol and caprylic acid and a monoester of glycerol and lauric acid, and typically the antimicrobial composition contains these four monoglycerides.

In one embodiment, the antimicrobial composition of the invention comprises at least one monoglycerol ester of a fatty acid, wherein the monoglycerol ester of a fatty acid comprises: between 5% and 20% by weight of a monoester of glycerol and butyric acid, preferably between 5% and 15% by weight, more preferably between 7% and 12% by weight, most preferably 10% by weight; and/or between 1% and 3% by weight of a monoester of glycerol and capric acid, preferably between 1% and 2% by weight, more preferably between 1% and 1.5% by weight, most preferably 1.4% by weight; and/or between 0.5% and 2% by weight of a monoester of glycerol and caprylic acid, preferably between 0.5% and 1.5% by weight, more preferably between 0.8% and 1.2% by weight, most preferably 1% by weight; and/or between 2.5% and 4% by weight of a monoester of glycerol and lauric acid, preferably between 3% and 4% by weight, more preferably between 3% and 3.5% by weight, most preferably 3.2% by weight, wherein the amount of the monoglycerol ester of a fatty acid is based on the total weight of the antimicrobial composition.

In particular, the ethyl lauroyl arginate comprised by the antimicrobial composition of the invention is ethyl lauroyl arginate hydrochloride, although other salts of ethyl lauroyl arginate are also part of the invention, as far as those ethyl lauroyl arginate salts are non-hazardous salts and are acceptable for use in an antimicrobial composition suitable for use in cleaning, decontaminating, preventing from microbial overgrowth, etc., of a surface which for example contacts human skin, food and food products, surface water, etc., when routinely and regularly applied and in use. Typically, the antimicrobial composition of the invention comprises between 3% and 5% by weight ethyl lauroyl arginate hydrochloride, preferably between 3.5% and 4.5% by weight, more preferably between 4% and 4.5% by weight, most preferably about 4% by weight, based on the total weight of the antimicrobial composition.

An embodiment is the antimicrobial composition of the invention, wherein the antimicrobial composition further comprises one or more of: (a) glycerol, preferably between 40% and 60% by weight, more preferably between 50% and 60% by weight, most preferably between 50% and 55% by weight, such as 52% by weight; (b) propylene glycol, preferably between 2% and 4% by weight, more preferably between 2.5% and 3.5% by weight, most preferably between 3% and 3.5% by weight, such as 3% by weight; (c) acetic acid, preferably between 5% and 20% by weight, more preferably between 5% and 15% by weight, most preferably between 7% and 12% by weight, such as 10% by weight; and (d) water, preferably between 5% and 20% by weight, more preferably between 5% and 15% by weight, most preferably between 7% and 12% by weight, such as 10% by weight, wherein the amount of glycerol, propylene glycol, acetic acid and water each is based on the total weight of the antimicrobial composition. Glycerol may be comprised by the antimicrobial composition according to the invention, for its activity as a humectant and/or the glycerol is comprised by the antimicrobial composition as a solvent for e.g. the monoglycerides, fatty acids or salts thereof and/or the ethyl lauroyl arginate such as ethyl lauroyl arginate hydrochloride. Preferably, the antimicrobial composition comprises glycerol according to the invention. Propylene glycol may be comprised by the antimicrobial composition according to the invention, for its activity as a humectant and/or the propylene glycol is comprised by the antimicrobial composition as a solvent for e.g. the monoglycerides, fatty acids or salts thereof and/or the ethyl lauroyl arginate such as ethyl lauroyl arginate hydrochloride. Preferably, the antimicrobial composition comprises propylene glycol according to the invention. Acetic acid may be comprised by the antimicrobial composition according to the invention, for adjusting or setting the pH of the antimicrobial composition to a desired value, e.g. about 4-10, and/or the acetic acid is comprised by the antimicrobial composition as a solvent for e.g. the monoglycerides, fatty acids or salts thereof and/or the ethyl lauroyl arginate such as ethyl lauroyl arginate hydrochloride. Preferably, the antimicrobial composition comprises acetic acid according to the invention. Water may be comprised by the antimicrobial composition according to the invention, as a solvent for e.g. the monoglycerides, fatty acids or salts thereof and/or the ethyl lauroyl arginate such as ethyl lauroyl arginate hydrochloride and the water may be part of the antimicrobial composition as a diluent and/or carrier.

In certain embodiments, the antimicrobial composition of the invention further comprises a fatty acid and/or a salt thereof, preferably two or more different fatty acids or salts thereof, such as three or four fatty acids and/or salts thereof. Typically, these fatty acids are saturated fatty acids with four to twelve carbon atoms (C4:0 - 02:0, such as C4:0, C6:0, C8:0, 00:0 and 02:0). Preferably, the antimicrobial composition of the invention further comprises a fatty acid and/or a salt thereof, wherein the fatty acid is one or more of butyric acid (butanoic acid, C4:0), capric acid (decanoic acid, 00:0), caprylic acid (octanoic acid, C8:0) and lauric acid (dodecanoic acid, 02:0). Typically, the antimicrobial composition of the invention comprises two or three or four of butyric acid, capric acid, caprylic acid, lauric acid. In one embodiment, the antimicrobial composition according to the invention comprises one or more of the fatty acid and/or a salt thereof selected from: (a) between 2% and 5 % by weight butyric acid or a salt thereof, preferably between 2% and 4% by weight, more preferably between 3% and 4% by weight, most preferably 3.4% by weight; (b) between 0.1% and 2% by weight capric acid or a salt thereof, preferably between 0.1% and 1% by weight, more preferably between 0.1% and 0.5% by weight, most preferably 0.3% by weight; (c) between 0.1% and 2% by weight caprylic acid or a salt thereof, preferably between 0.1% and 1% by weight, more preferably between 0.1% and 0.5% by weight, most preferably 0.3% by weight; and between 1% and 3% by weight lauric acid or a salt thereof, preferably between 1% and 2% by weight, more preferably between 1% and 1.5% by weight, most preferably 1.4% by weight, wherein the amount of the fatty acid and/or the salt thereof is based on the total weight of the antimicrobial composition.

A preferred embodiment is the antimicrobial composition of the invention, comprising about 3.4% by weight butyric acid and/or a salt thereof, about 0.3% by weight capric acid and/or a salt thereof, about 0.3% by weight caprylic acid and/or a salt thereof, about 1.4% by weight lauric acid and/or a salt thereof, about 10% by weight monoester of glycerol and butyric acid, about 1.4% by weight monoester of glycerol and capric acid, about 1% by weight monoester of glycerol and caprylic acid, about 3.2% by weight monoester of glycerol and lauric acid, about 52% by weight glycerol, about 3% by weight propylene glycol, about 4% by weight lauroyl-ethyl-arginate-HCl (ethyl lauroyl arginate hydrochloride), about 10% by weight acetic acid and about 10% by weight water, based on the total weight of the antimicrobial composition. An antimicrobial composition of the invention contains 3.4% by weight butyric acid and/or a salt thereof, 0.3% by weight capric acid and/or a salt thereof, 0.3% by weight caprylic acid and/or a salt thereof, 1.4% by weight lauric acid and/or a salt thereof, 10% by weight monoester of glycerol and butyric acid, 1.4% by weight monoester of glycerol and capric acid, 1% by weight monoester of glycerol and caprylic acid, 3.2% by weight monoester of glycerol and lauric acid, 52% by weight glycerol, 3% by weight propylene glycol, 4% by weight lauroyl-ethyl-arginate-HCl (ethyl lauroyl arginate hydrochloride), 10% by weight acetic acid and 10% by weight water, based on the total weight of the antimicrobial composition.

In a preferred embodiment, the antimicrobial composition according to the invention comprises less than 0.6% by weight nitrogen based on the total weight of the antimicrobial composition and/or is free of phosphorus and/or is free of sulphur, preferably, the antimicrobial composition comprises less than 0.45% by weight nitrogen based on the total weight of the antimicrobial composition and is free of phosphorus and is free of sulphur. That is to say, in contrast to commonly applied detergent products known in the art, the antimicrobial composition of the invention is preferably free of phosphorus and is preferably free of sulphur and is preferably free of nitrogen or comprises an amount of nitrogen at lower than 1% by weight based on the total weight of the antimicrobial composition.

Nitrogen, phosphorus and sulphur are the main causative agents of eutrophication. Eutrophication is the process in which a body of water becomes overly enriched with minerals and nutrients. This causes amongst others overgrowth of plants and algae and can lead to oxygen depletion of the waterbody. Eventually, if left untreated, eutrophication will cause overcrowding of plants and algae, which in turn leads to all the organisms living in the body of water dying due to lack of oxygen. Thus, by avoiding the application of phosphorus and sulphur in the antimicrobial composition, the risk for eutrophication of water bodies by said composition is diminished. In addition, applying nitrogen in the antimicrobial composition only at relatively low dose also adds to lowering the risk for eutrophication when water is contacted with the composition of the invention.

It is preferred that the antimicrobial composition of the invention has a pH of between 4 and 10, preferably between 4-8, more preferably between 4-6, most preferably the pH is 4.55. Typically, the pH of the antimicrobial composition of the invention is between 4 and 5, such as about 4.55. The range of pH 4-10 for the antimicrobial composition of the invention is particularly preferred, since at pH lower than 4 and/or at pH higher than 10, constituents of said composition may decompose, such as de-esterification of monoglycerides. Furthermore, within the range of pH 4-10, salts of fatty acids applied in the antimicrobial composition of the invention have buffering capacity. In addition, within the preferred range of pH 4-10, such as 4.5-6, typically 4.55, the antimicrobial activity of the antimicrobial composition is optimal and the activity of its constituents is not compromised by a too low pH and/or by a too high pH.

A second aspect of the invention relates to a disinfectant, a sanitizer, a detergent, comprising the antimicrobial composition according to the invention and a diluent, preferably water. It is thus preferred that the disinfectant, the sanitizer and the detergent of the invention are a fluid such as an aqueous solution.

Typically, the disinfectant, the sanitizer and the detergent of the invention comprising the antimicrobial composition according to the invention comprise at least 0.2% by weight of said antimicrobial composition based on the total weight of the disinfectant, preferably between 0.3% and 25% by weight, more preferably between 0.5% and 5% by weight, most preferably between 0.7% and 4% by weight, such as 0.75% by weight, 1.5% by weight and 3% by weight, based on the total weight of the disinfectant, the sanitizer or the detergent. It is preferred that the disinfectant, the sanitizer or the detergent of the invention comprise for example about 0.375% by weight of the antimicrobial composition of the invention, based on the total weight of the disinfectant, the sanitizer or the detergent, more preferably about 0.75% by weight or more, such as about 0.75% by weight, about 1.5% by weight, about 3% by weight, based on the total weight of the disinfectant, the sanitizer or the detergent. In addition, it is also part of the invention that the use of the antimicrobial composition according to the invention in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, encompasses the step of adding the antimicrobial to the aqueous solution to a final concentration of less than 0,2% by weight of the antimicrobial composition based on the total weight of the aqueous solution, such as 0,15%, 0,125%, 0,1%, 0,075%, 0,05% or lower, based on the total weight of the aqueous solution, such as 0,025-0,2% by weight.

An advantage of using the antimicrobial composition of the invention in the decontamination of water is that it does not contain any elements that are known to be harmful to the environment and/or to human health. Other products known in the art and which are used in the decontamination of water, i.e. discarding microorganisms from water by killing the microorganisms and/or preventing growth of microorganisms in water, either contain QACs, or contain components that can form DBPs, or both. Both these categories of compounds are harmful to the environment and/or to human health. Additionally, the antimicrobial composition of the invention does not cause eutrophication in contaminated water bodies treated with the antimicrobial composition since the amount of nitrogen present in the antimicrobial composition is relatively low and/or since the antimicrobial composition of the invention is free of phosphorus and/or is free of sulphur. Preferably, the antimicrobial composition of the invention does not comprise phosphorus, does not comprise sulphur and comprises nitrogen at low amount, i.e. less than 0.6% by weight nitrogen based on the total weight of the antimicrobial composition, such as about 0.44% by weight nitrogen.

In a preferred embodiment, the disinfectant, the sanitizer or the detergent of the invention have antimicrobial activity against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and Legionella pneumophila. It is preferred that the disinfectant, the sanitizer and/or the detergent of the invention have antimicrobial activity towards at least two or more, such as two, three or four of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and Legionella pneumophila. Typically, the disinfectant, the sanitizer and/or the detergent of the invention is capable of killing all four pathogens Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and Legionella pneumophila.

A third aspect of the invention relates to the use of the antimicrobial composition of the invention or the use of the disinfectant, the sanitizer and/or the detergent of the invention, comprising said antimicrobial composition, in purification of air contaminated with a microbe such as a bacterium, preferably in the purification of air by water tank-based air purification.

A fourth aspect of the invention relates to the use of the antimicrobial composition of the invention or the use of the disinfectant, the sanitizer and/or the detergent of the invention, comprising said antimicrobial composition, in decontaminating a surface contaminated with a microbe such as a bacterium and/or in preventing a surface from contamination with a microbe such as a bacterium. An example is the use of the disinfectant, the sanitizer or the detergent, wherein the surface is a surface of a body such as a human body, such as the hand of a human subject.

A fifth aspect of the invention relates to the use of the antimicrobial composition of the invention or the use of the disinfectant, the sanitizer and/or the detergent of the invention, comprising said antimicrobial composition, in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, a mould or a yeast or in preventing an aqueous solution such as water from becoming contaminated with a microbe such as a bacterium, a mould or a yeast, wherein the antimicrobial composition or the disinfectant, the sanitizer or the detergent is added to the aqueous solution at a concentration of at least 0.2% by weight of the antimicrobial composition based on the total weight of the aqueous solution, preferably between 0.3% and 25% by weight, more preferably between 0.5% and 5% by weight, most preferably between 0.7% and 4% by weight, such as 0.75% by weight, 1.5% by weight and 3% by weight, based on the total weight of the aqueous solution. It is preferred that the antimicrobial composition is applied at a final concentration of for example about 0.375% by weight or about 0.75% by weight based on the total weight of the aqueous solution, when used in decontamination of said aqueous solution and/or when used for preventing the aqueous solution from becoming contaminated or even overgrown by microbes such as bacteria, according to the invention. Alternatively, the use of the antimicrobial composition of the invention or the use of the disinfectant, the sanitizer and/or the detergent of the invention, comprising said antimicrobial composition, in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, a mould or a yeast or in preventing an aqueous solution such as water from becoming contaminated with a microbe such as a bacterium, a mould or a yeast, wherein the antimicrobial composition or the disinfectant, the sanitizer and/or the detergent is added to the aqueous solution at a concentration of 0.25% or lower by weight of the antimicrobial composition based on the total weight of the aqueous solution, preferably between 0.01% and 0,25% by weight, more preferably between 0.025% and 0,2% by weight, most preferably between 0.05% and 0,15% by weight, such as 0.075% by weight, 0,1% by weight and 0,125% by weight, based on the total weight of the aqueous solution. Preferably, the antimicrobial composition of the invention or the disinfectant, the sanitizer and/or the detergent of the invention, applied for this use according to the invention has antimicrobial activity against at least Legionella pneumophila. Of course, it is even more preferred that the antimicrobial composition or the disinfectant, the sanitizer and the detergent comprising said antimicrobial composition has antimicrobial activity to further microbes such as one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica.

Legionella pneumophila is one of the biggest dangers in water systems. It can cause serious disease in human beings, which in some cases can even be fatal. Eliminating this contaminant from a water system would greatly improve the safety of using said water in an environment where humans will come into contact with it.

An advantage of the disinfectant, the sanitizer and the detergent of the invention is that the composition according to the invention, as mentioned before, does not comprise compounds that can produce DBPs, nor does it contain QACs, which means that the health and environmental risks associated with these compounds are not present in the composition of the disinfectant, the sanitizer and the detergent of the invention. Therefore, the disinfectant, the sanitizer and the detergent of the invention have the advantage over commercially available disinfectants, sanitizers and detergents of not possessing these health risks and environmental risks.

Another advantage of using the antimicrobial composition of the invention in the disinfectant, the sanitizer and the detergent of the invention is that the composition of the invention uses monoglycerides instead of the commonly used free fatty acids. The efficacy of fatty acids party relies on an active antimicrobial action due to the disruption of bacterial cells and partly on the acidification of the solution comprising said fatty acids. The efficacy of monoglycerides is based completely on their antimicrobial activity. It has been found that the use of monoglycerides therefore increases the efficiency of the disinfectant, the sanitizer and the detergent of the invention over disinfectants, sanitizers and detergents comprising free fatty acids.

Commonly available disinfectants, sanitizers and detergents often include nitrogen, phosphorus and sulphur. These three elements are the main causative agents of eutrophication as explained here above. Surprisingly the inventors found that leaving phosphorus and sulphur out of the composition and using only a relatively low concentration of nitrogen had no negative effect on the antimicrobial activity of the antimicrobial composition of the invention.

The inventors have surprisingly found that using the disinfectant of the invention in a water tank-based air purification system is beneficial to the quality of the purified air exiting the air purification system and entering a room in which the air purification system is operating. Accumulation of microbial contaminants can occur in the water tank of the air purification system through which air is led as part of the purification process. These contaminating microbes can in turn be carried into the environment, e.g. a room, by this air leaving the air purification system. Adding the antimicrobial composition of the invention to the water tank of the air purifier significantly improved the quality of the purified air leaving the system, when comparing with the microbial load of the air purified in a similar system using commercially available disinfectants in the water.

The inventors have found that using the disinfectant, the sanitizer and the detergent of the invention on contaminated surfaces can slow down recontamination of said surface after pre-cleaning of the surface with the disinfectant, the sanitizer or the detergent. Additionally, the disinfectant, the sanitizer or the detergent of the invention is also capable of effectively eliminating all contamination by microorganisms by cleaning a contaminated surface with said disinfectant, sanitizer or detergent.

The observed decontamination activity and prevention of recontamination activity of the disinfectant, the sanitizer or the detergent of the invention comprising the antimicrobial composition of the invention is useful in applications where contaminated surfaces are considered hazardous, such as surfaces applied in food processing and packaging, or surfaces exposed in a medical context such as hospital floors, operation rooms, implant surfaces, etc., and application of the disinfectant, the sanitizer or the detergent of the invention increases the time period after which cleaning of a previously cleaned surfaces becomes necessary again. In a preferred embodiment of the invention, the disinfectant, the sanitizer and/or the detergent is active against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and/or Legionella pneumophila. All of these pathogens are capable of infecting humans and causing serious disease in a human host. The pathogens can be transmitted to humans via contaminated carriers such as the surface of an article, an object, such as a floor, a desk, a door grip, etc., and therefore it is of great importance that prevention or elimination of contamination with these pathogens in or on these carriers is possible. The inventors now provide an efficient and efficacious disinfectant, sanitizer and detergent capable of preventing the growth of these pathogens to a large extent, or cleaning a surface, such as the hands of a human subject from these pathogens.

The disinfectant, the sanitizer and/or the detergent of the invention is microbially active against at least the aforementioned four types of pathogens and therewith the disinfectant, the sanitizer and/or the detergent is of aid in the prevention against overgrowth of surfaces by these pathogens or elimination of these pathogens contaminating a certain surface.

While the invention has been described in terms of several embodiments, it is contemplated that alternatives, modifications, permutations and equivalents thereof will become apparent to one having ordinary skill in the art upon reading the specification. The invention is not limited in any way to the illustrated and described embodiments. Changes can be made without departing from the scope which is defined by the appended claims.

The invention is further illustrated by the following examples, which should not be interpreted as limiting the present invention in any way.

EXAMPLES

Preparation of an exemplifying antimicrobial composition: antimicrobial composition COMPOSITION A

An antimicrobial composition was made to be used in the following Examples, and is referred to as “COMPOSITION A”. The antimicrobial composition COMPOSITION A comprises the following components:

• 3.4% by weight butyric acid or its salts 0.3% by weight capric acid or its salts

0.3% by weight caprylic acid or its salts

1.4% by weight lauric acid or its salts

10% by weight monoester of glycerol and butyric acid

1.4% by weight monoester of glycerol and capric acid

1% by weight monoester of glycerol and caprylic acid

3.2% by weight monoester of glycerol and lauric acid

52% by weight glycerol

3% by weight propylene glycol

4% by weight ethyl lauroyl arginate hydrochloride (LAE®; Vedeqsa, Barcelona, Spain)

10% by weight acetic acid

10% by weight water,

all based on the total weight of the antimicrobial composition COMPOSITION

A.

LAE® is also marketed as MIRENAT® and is ethyl lauroyl arginate hydrochloride.

Example 1

A series of experiments was conducted to compare the activity of an exemplifying antimicrobial composition, referred to as COMPOSITION A, when applied as a disinfectant or when applied in the preparation of a disinfectant.

For example, the antimicrobial activity of diluted COMPOSITION A was compared with the antimicrobial activity of quaternary ammonium salts, a compound that is commonly used in disinfectants as the active ingredient, in an air purifier. The quaternary ammonium salt-containing disinfectant used was Aroquat (Firma S.r.l, Correggio, Italy), which contains 10 wt% of quaternary ammonium salts based on the total weight of said disinfectant, from now on referred to as“CONTROL QAS”.

An air purifying system was used that purifies air by passing it through a thin water veil. The water that circulates in the system is stored in a tank that must contain disinfectant or detergent products to avoid increasing contamination of the water as it is re-used. Typically, the water in such tank is at risk of becoming contaminated and even overgrown by microbes such as bacteria, for example Legionella pneumophila.

The air purifying system was placed in a 60 m² room, the room having a volume of 200 m³, where the temperature was between 23-25°C with a relative humidity of 44.1%. First, the CONTROL QAS was prepared by dissolving it in the water present in the air purifier to a concentration of 2% by weight in water based on the total weight of the water in the air purifier. Under similar conditions, the composition was prepared by dissolving the antimicrobial composition COMPOSITION A in the water present in the air purifier to a concentration of 0.75% by weight in water based on the total weight of the water in the air purifier.

For each experiment four human subjects each entered the room and left again at least ten times, adding up to a total of at least 40 entrances, to promote activity in the air purifier, wherein the human subjects stayed in the room for between 30 minutes and 60 minutes each time after entering the room.

The efficacy of COMPOSITION A was compared with that of CONTROL QAS, and the efficacy with regard to antimicrobial activity was evaluated by measuring total microbial load of the water in the tank (Example 1A), total microbial load of purified air leaving the machine (Example IB), and total microbial load of the environmental air in the room in which the air purifier (Example 1C).

Sampling was performed at different times during the period in which the air purifier was active. Samples were taken of the water, purified air and environmental air at 1 minute after starting the air purifier (TO), 1 hour after starting it (Tl), 3 hours after starting (T3), 4 hours after starting (T4), 5 hours after starting (T5), and 24 hours after starting (T24).

Example 1A

The water from the tank was analysed following the ISO 6222: 1999 protocol. The water was plated onto a PCA cas N° 70152 medium (Biolife, Milan, Italy) in a petri dish and incubated at 30°C for 24, 48 and 72 hours to assure no late growth of microorganism species was missed. Yeasts and especially moulds are very important contributors to air contamination. The prolongation of the incubation time is therefore oriented to allow delayed growth of moulds rather than of bacteria, because moulds have slower growth rate. In Table 1, the averaged results measured are depicted. Petri dishes are incubated for 72 hours to allow eukaryotic microbes to growth, if present.

The results of the water sample measurements of the CONTROL QAS and the COMPOSITION A are shown below in Table 1. Values for the total

microbial loads are shown in CFU/ml.

Table 1

The microbial loads of the water in the tank containing the COMPOSITION A were significantly lower than those of the water in the tank containing the CONTROL QAS. This shows that COMPOSITION A is much more effective in preventing and eliminating contamination of water than the commercially available disinfectant with regard to the presence and number of microorganisms in the water in the tank during the time course of 1/2/3/4/5/24 hours of incubation.

Example IB

The air samples of the air exiting the air purifier were analysed with a SAS super IAQ for Petri (VWR, Milan, Italy). Samples of 200 m³ air were collected and plated onto a PC A cas N° 70152 medium in a petri dish and incubated at 30°C for 24, 48 and 72 hours to assure no late growth of microorganism species was missed. Petri dishes are incubated for 72 hours to allow eukaryotic microbes to growth, if present. The results of the purified air from the air purifier measurements of the Aroquat and the composition of the invention are shown below in Table 2. Values for the total microbial loads are shown in CFU/m³.

Table 2

The air leaving the air purifier which contains the water comprising COMPOSITION A is not becoming more contaminated during the time course of the experiment when compared to the microbial load at the start of the experiment (TO), whereas in contrast an increasing contamination with microorganisms is apparent for the air leaving the air purifier containing the water comprising CONTROL QAS. This shows that COMPOSITION A is capable of combating contamination over a much longer time span than the conventional disinfectant CONTROL QAS, and that COMPOSITION A is efficient and efficacious in preventing the air leaving the air purifier in operation from becoming contaminated with microbes such as bacteria, for at least a time span of 24 hours, whereas for CONTROL QAS, the air leaving the air purifier is already becoming contaminated with microbes after already four hours after the start of the experiment and starting operation of the air purifier.

Example 1C

The results of the determination of the microbial load in the environmental air in the room in which the air purifier was operating for the indicated time frames are shown below in Table 3 for both the air in the room in which the air purifier was provided with water comprising CONTROL QAS and the air in the room in which the air purifier was provided with water comprising COMPOSITION A. Values for the total microbial loads are shown in CFU/m³. Petri dishes are incubated for 72 hours to allow eukaryotic microbes to growth, if present. Table 3

Both the environmental air in the room surrounding the air purifier in operation and containing water comprising comparative disinfectant CONTROL QAS and the environmental air in the room surrounding the air purifier in operation containing the water comprising antimicrobial composition COMPOSITION A comprise less microorganisms from TO onwards when compared to the initial microbial load of the air in the room at TO. However, only COMPOSITION A is efficient and efficacious in maintaining the low level of microbial load reached already at T1 for the duration of the experiment up to at least T24. In contrast, when applying disinfectant CONTROL QAS in the air purifier, the lowest level of microbial load in the air in the room in which the air purifier is operating is only achieved at T3, and moreover, the extent of this lowest level of microbial load in the air in the room is not reaching the low level achieved with the air purifier provided with COMPOSITION A, already earlier at Tl. In addition, the air in the room in which the air purifier operates that comprises water with CONTROL QAS is becoming re-contaminated again after the initial decrease of the microbial load in the air in the room.

Conclusion

The data in Tables 1, 2 and 3 altogether show that the COMPOSITION A is more efficient and more efficacious in keeping the water in the tank of the air purifier free of contamination. The operation of the air purifier that was provided with water comprising CONTROL QAS as the disinfectant showed a clear and higher increase in contamination of the water in the water tank, which ultimately also negatively affected the purified air exiting the air purifier in that microbial load of the air increased during the time course of the experimental operation of the air purifier. In addition, the air present in the room in which the air purifier provided with water comprising CONTROL QAS was operating, was increasingly re-contaminated with microorganisms, i.e. the microbial load in the air in the room was increasing after an initial partial decrease, compared to the extent of the decrease and the extent of recontamination obtained with the air purifier provided with water comprising COMPOSITION A.

The COMPOSITION A was capable of keeping the microbial load low in the water tank of the air purifier, which in turn resulted in a low microbial load of the purified air and of the environmental air low as well. No clear increase in contamination was observed in either of the air samples from the room in which the air purifying system containing the COMPOSITION A was present, while a strong increase in microbial load of both air samples was observed after 5 hours when using CONTROL QAS.

This shows that the COMPOSITION A is more effective in preventing contamination, during a longer time period, than the state of the art product.

EXAMPLE 2

Varying concentrations of cleanser in water including negative control are tested as well as the performance of the cleanser at varying incubation temperatures. In this example, the water tank had the upper side open to allow contamination from the environment, and the water tank was not connected to the air purifier so there was no cycle of environmental air from the room passing the water. This way, it is to be expected that the microbial load is generally lower after an indicated amount of time, when compared to the microbial load in the water as observed in the previous examples, when air was passing the water in the water tank of the air purifier.

Results are provided in Table 4.

Table 4: microbial load in water comprising no anti-microbial agent, or an anti microbial agent, after incubation for 0, 24 and 48 hours at room temperature, wherein microbial load expressed as CFU/M1

All the tested formulations drastically reduce the initial microbial charge and maintain it clean up to 2 days. In the water in which an anti-microbial agent is not provided, during the course of time, the microbial load increases. From the experimental data it is obvious that the COMPOSITION A is still fully active with regard to antimicrobial activity when diluted to 0,25% by weight based on the total weight of the cleanser, indicating that COMPOSITION A is active at even further dilutions.

The same test was also performed at 4°C and 37°C, providing similar results: the 37°C incubator and the 4°C fridge are closed containers comprising the water tank and microbes were present only in untreated water after 2 days (410 colonies in the fridge at 4°C, 200 colonies in the incubator at 37°C. Thus, the CONTROL QAS and the COMPOSITION A at the indicated dilutions in the water present in the water tank are similarly effective in preventing microbial growth at all three temperatures tested.

Example 3

An antimicrobial activity of the composition was tested for antimicrobial activity against four different pathogenic bacteria: Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium. At least Campylobacter jejuni, Escherichia coli and Salmonella enterica serovar Typhimurium are related to food poisoning. The Kirby-Bauer Diffusion Test was used to determine the sensitivity or resistance of pathogenic aerobic and facultative anaerobic bacteria to the diluted COMPOSITION A, i.e. a‘DISINFECTANT A’, or‘DETERGENT A’.

For this experiment the COMPOSITION A was diluted in water such that a DISINFECTANT A was obtained, to a final concentration of 0.75% by weight based on the total weight of the DISINFECTANT A. This DISINFECTANT A was then applied on a paper disc with a diameter of 5 mm, which paper disc was positioned in the centre of a petri dish containing Mueller-Hinton agar medium (Sigma Aldrich). Next, 100 micro liters of a physiological solution with a microbial load of one of these four pathogens Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium of lxlO⁷ CFU/ml was applied to the medium on the petri dish. The petri dish was then incubated at 30°C for 24 hours.

Presence or absence of growth of the individually tested pathogens around the paper disc will indicate whether the antimicrobial solution DISINFECTANT A, i.e. the COMPOSITION A now diluted in water, has the ability to inhibit growth of the particular pathogens.

After the incubation for 24 hours at 30°C, it was seen that DISINFECTANT A is efficiently capable of inhibiting growth of all four pathogens. Inhibitory activity of DISINFECTANT A with regard to growth of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium was apparent based on the petri dishes showing an inhibition halo, which is an area free of pathogen growth, around at least the immediate area surrounding the paper disc. For Campylobacter jejuni, the halo around the paper disc extended to about 1.1 mm to about 2 mm from the edge of the paper disc, whereas the remainder of the medium was almost completely overgrown with bacteria. For Escherichia coli, the halo around the paper disc extended to about 1 mm to about 2.2 mm from the edge of the paper disc, whereas the remainder of the medium was completely overgrown with bacteria. For Listeria monocytogenes, the halo around the paper disc extended to about 2.5 mm to about 7 mm from the edge of the paper disc, whereas the remainder of the medium was completely overgrown with bacteria. For Salmonella enterica serovar Typhimurium, the halo around the paper disc extended evenly over about 1 mm from the edge of the paper disc with decreased growth in a further halo around the paper disc extending to between about 2 mm and 10 mm, whereas the remainder of the medium was completely overgrown with bacteria. This observation confirms that the DISINFECTANT A, i.e. the aqueous solution containing the diluted COMPOSITION A at a concentration of 0.75% by weight based on the total weight of the DISINFECTANT A, has antimicrobial activity against at least the four bacteria tested, and at least for the duration of the test.

The highest antimicrobial activity was seen in the petri dish in which Listeria monocytogenes had been inoculated, the pathogen Listeria monocytogenes known as a food contaminant and known for listeriosis activity.

Example 4

A Kirby-Bauer Diffusion Test was conducted with the COMPOSITION A diluted in water, providing a‘DISINFECTANT Bl-4’, or‘DETERGENT Bl- 4’, to test the activity of DISINFECTANT Bl-4 with regard to the capability to inhibit growth of Legionella pneumophila. The COMPOSITION A was dissolved in water at four different concentrations, providing DISINFECTANT Bl, DISINFECTANT B2, DISINFECTANT B3 and DISINFECTANT B4, respectively: 0.375% by weight COMPOSITION A, 0.75% by weight COMPOSITION A, 1.5% by weight COMPOSITION A and 3% by weight COMPOSITION A, based on the total weight of DISINFECTANT Bl-4, respectively.

Similar to the experiment conducted in Example 2, the four solutions DISINFECTANT Bl-4 were each applied to a separate paper disc with a diameter of 5 mm. These four discs were then applied to a petri dish containing BCYE Agar (VWR Chemical, Milan, Italy), i.e. the discs were positioned on top of the agar surface in the petri dish, which agar surface was then inoculated with 100 microliters of a physiological solution containing the Legionella pneumophila bacteria at a microbial load of 1x107 CFU/ml. The petri dishes were subsequently incubated for 72 hours at 35°C.

After said incubation the petri dishes were analysed and the inhibition halo around the paper discs was measured for each different concentration of diluted COMPOSITION A, i.e. DISINFECTANT Bl-4. The results of these measurements are provided below in Table 5.

Table 5

All four dilutions tested of COMPOSITION A, i.e. DISINFECTANT Bl-4, had efficient and efficacious activity against Legionella pneumophila, when inhibition of bacterial growth is considered. Contamination with Legionella pneumophila, or even overgrowth by Legionella pneumophila is one of the biggest dangers in (closed) water systems. The higher the concentration of COMPOSITION A in the DISINFECTANT B, the higher the growth-inhibitory activity against the pathogen, and from the test it is evident that even at the lowest concentration of COMPOSITION A tested, already a significant growth- inhibitory activity against the pathogen is achieved, which shows that the DISINFECTANT B has antimicrobial activity also at low concentrations of COMPOSITION A.

Example 5

The level of recontamination of a desk was analysed, i.e. the capability of an antimicrobial composition of the invention to prevent a surface of e.g. an article such as a desk from contamination by a pathogen or overgrowth by microbes. The microbial load of a desk surface either made of steel or made of a ceramic that was not cleaned was compared to the microbial load of a desk surface that was cleaned once with the COMPOSITION A diluted in water such that ‘DISINFECTANT C\ or ‘DETERGENT C’ was provided. The DISINFECTANT C was applied directly on the desk surface and then wiped off. For preparing DISINFECTANT C, the COMPOSITION A was dissolved in water to a final concentration of 0.75% by weight based on the total weight of DISINFECTANT C, and DISINFECTANT C was then applied onto the desk surface. The temperature was 25°C during the experiment. The microbial loads of the two desk surfaces, i.e. the uncleaned Comparative example desk surface and the desk surface treated with DISINFECTANT C, are shown below in Table 6. The measurements of microorganism load are shown. The measurements are the average number of microbes counted at three separate areas that have been sampled.

Table 6

The microbial counts depicted in Table 6 show that at all time points the desk cleaned with the DISINFECTANT C has a lower extent of contamination with microorganisms (bacteria) than the desk that had not been cleaned up before the start of the experiment, the growth-inhibitory activity of DISINFECTANT C lasting to at least 24 hours after cleaning. After 24 hours from the start of the experiment, the number of counted microorganisms in CFU/m² is about 23-fold lower for the desk surface treated with DISINFECTANT C compared with the comparative example desk surface. Six hours after the start of the experiment, DISINFECTANT C is even about 69 times more effective in preventing the desk surface from overgrowth by microorganisms. At the start of the experiment, the desk surface treated with DISINFECTANT C is even completely free of microorganisms, showing the high efficiency and efficacy of DISINFECTANT C with regard to removing microorganisms such as pathogens like bacteria from the surface of an article such as a desk. This indicates that the composition of the invention has a long-lasting effect in preventing recontamination of surfaces it is used on.

Example 6

In a similar experiment to Example 5, the ability of the DISINFECTANT C to eliminate microorganisms present on a surface of an object or article and to inhibit regrowth of microorganisms on a previously cleaned surface applying DISINFECTANT C, was tested using three different surfaces: one desk surface and two floor surfaces made of ceramic. On sections of each of these surface, 10 mL/m² water as the reference was applied for providing the cleaning control, and on different sections of these surfaces 10 mL/m² DISINFECTANT C was applied. For each of the three surfaces, part of the surface was left untreated/uncleaned and part of the surface was thus cleaned with DISINFECTANT C. Then, the three surfaces were incubated for 48 hours at 30°C. After this incubation, the uncleaned and cleaned surface areas were analysed for the microorganism load, to establish the growth-inhibitory activity of DISINFECTANT C determined by the extent of microbial load. The microbial loads for each surface after the incubation for 48 h are shown below in Table 7.

The diluted COMPOSITION A, i.e. DISINFECTANT C, is highly effective in eliminating contamination from the three surfaces tested when compared to uncleaned surfaces, and is highly effective in preventing surfaces cleaned with DISINFECTANT C from regrowth and recontamination with microorganisms during at least 48 h. This shows that DISINFECTANT C is suitable for use as a disinfectant in cleaning surfaces of articles and objects, discarding microbes such as bacteria from said surfaces, and for use in preventing surfaces from becoming colonized by microbes.

Table 7

Example 7

To show the synergistic action, i.e. anti-microbial activity, of components of COMPOSITION A, an experiment similar to EXAMPLE 2, including negative control, was performed, comparing decreasing concentrations of 3 compositions: COMPOSITION A, a solution of LAE 4% w/w in glycerol, and a blend of monoglycerides and fatty acids with the same concentrations of monoglycerides and fatty acids as in COMPOSITION A. The synergistic action of the different components is shown at the concentration of the individual components as also present in 0,1% of COMPOSITION A. At this concentration, corresponding to 0,004% of LAE and 0,04% of monoglycerides and fatty acids, the antimicrobial effect of diluted COMPOSITION A is higher in comparison with the corresponding concentrations of LAE and monoglycerides alone. That is to say, after the incubation of water in a tank for 6-24 h at 30 DC, the COMPOSITION A is capable of maintaining the microbial load at 0, whereas incubation a same volume of water comprising either 0,004% LAE by weight of the solution, or 0,04% monoglycerides and fatty acids by weight of the solution, results in the presence of microbes detectable in the water comprising the LAE or the monoglycerides and fatty acids.

Results are provided in Table 8.

Claims

CLAIMS 1) An antimicrobial composition comprising: (a) at least one monoglycerol ester of a fatty acid; and (b) ethyl lauroyl arginate. 2) The antimicrobial composition of claim 1, wherein the monoglycerol ester of a fatty acid is/are selected from a monoester of glycerol and butyric acid, capric acid, caprylic acid or lauric acid. 3) The antimicrobial composition of claim 1 or 2, wherein the monoglycerol ester of a fatty acid comprises a monoester of glycerol and butyric acid, a monoester of glycerol and capric acid, a monoester of glycerol and caprylic acid and a monoester of glycerol and lauric acid. 4) The antimicrobial composition of any one of claims 1-3, wherein the monoglycerol ester of a fatty acid comprises: between 5% and 20% by weight of a monoester of glycerol and butyric acid, preferably between 5% and 15% by weight, more preferably between 7% and 12% by weight, most preferably 10% by weight; and/or between 1% and 3% by weight of a monoester of glycerol and capric acid, preferably between 1% and 2% by weight, more preferably between 1% and

1.5% by weight, most preferably 1.4% by weight; and/or

between 0.5% and 2% by weight of a monoester of glycerol and caprylic acid, preferably between 0.5% and 1.5% by weight, more preferably between 0.8% and 1.

2% by weight, most preferably 1% by weight; and/or

between 2.5% and 4% by weight of a monoester of glycerol and lauric acid, preferably between 3% and 4% by weight, more preferably between 3% and

3.5% by weight, most preferably 3.2% by weight,

wherein the amount of the monoglycerol ester of a fatty acid is based on the total weight of the antimicrobial composition.

5) The antimicrobial composition of any one of claims 1-4, wherein the ethyl lauroyl arginate is ethyl lauroyl arginate hydrochloride.

6) The antimicrobial composition of any one of claims 1-5, wherein the antimicrobial composition comprises between 3% and 5% by weight ethyl lauroyl arginate hydrochloride, preferably between 3.5% and 4.5% by weight, more preferably between 4% and 4.5% by weight, most preferably 4% by weight, based on the total weight of the antimicrobial composition.

7) The antimicrobial composition of any one of claims 1-6, wherein the antimicrobial composition further comprises one or more of:

(a) glycerol, preferably between 40% and 60% by weight, more preferably between 50% and 60% by weight, most preferably between 50% and 55% by weight, such as 52% by weight;

(b) propylene glycol, preferably between 2% and 4% by weight, more preferably between 2.5% and 3.5% by weight, most preferably between 3% and 3.5% by weight, such as 3% by weight;

(c) acetic acid, preferably between 5% and 20% by weight, more preferably between 5% and 15% by weight, most preferably between 7% and 12% by weight, such as 10% by weight; and

(d) water, preferably between 5% and 20% by weight, more preferably between 5% and 15% by weight, most preferably between 7% and 12% by weight, such as 10% by weight,

wherein the amount of glycerol, propylene glycol, acetic acid and water each is based on the total weight of the antimicrobial composition.

8) The antimicrobial composition of any one of claims 1-7, wherein the antimicrobial composition further comprises a fatty acid and/or a salt thereof.

9) The antimicrobial composition according to claim 8, wherein the fatty acid is one or more of butyric acid, capric acid, caprylic acid and lauric acid.

10) The antimicrobial composition according to claim 8 or 9, wherein the antimicrobial composition comprises one or more of the fatty acid and/or a salt thereof selected from:

(a) between 2% and 5 % by weight butyric acid or a salt thereof, preferably between 2% and 4% by weight, more preferably between 3% and 4% by weight, most preferably 3.4% by weight;

(b) between 0.1% and 2% by weight capric acid or a salt thereof, preferably between 0.1% and 1% by weight, more preferably between 0.1% and 0.5% by weight, most preferably 0.3% by weight; (c) between 0.1% and 2% by weight caprylic acid or a salt thereof, preferably between 0.1% and 1% by weight, more preferably between 0.1% and 0.5% by weight, most preferably 0.3% by weight; and between 1% and 3% by weight lauric acid or a salt thereof, preferably between 1% and 2% by weight, more preferably between 1% and 1.5% by weight, most preferably 1.4% by weight,

wherein the amount of the fatty acid and/or the salt thereof is based on the total weight of the antimicrobial composition.

11) The antimicrobial composition according any one of the preceding claims, wherein the antimicrobial composition comprises less than 0.6% by weight nitrogen based on the total weight of the antimicrobial composition and/or is free of phosphorus and/or is free of sulphur, preferably, the antimicrobial composition comprises less than 0.45% by weight nitrogen based on the total weight of the antimicrobial composition and is free of phosphorus and of sulphur.

12) The antimicrobial composition according to any one of the preceding claims, wherein the antimicrobial composition has a pH of between 4 and 10, preferably between 4-8, more preferably between 4-6, most preferably 4.55.

13) A disinfectant, sanitizer or detergent comprising:

(a) the antimicrobial composition according to any one of the preceding claims; and

(b) a diluent, preferably water.

14) The disinfectant, sanitizer or detergent according to claim 13, wherein the disinfectant, sanitizer or detergent comprises at least 0.2% by weight of the antimicrobial composition based on the total weight of the disinfectant, sanitizer or detergent, preferably between 0.3% and 25% by weight, more preferably between 0.5% and 5% by weight, most preferably between 0.7% and 4% by weight, such as 0.75% by weight, 1.5% by weight and 3% by weight, based on the total weight of the disinfectant, sanitizer or detergent.

15) The disinfectant, sanitizer or detergent according to claim 13 or 14, wherein the disinfectant, sanitizer or detergent has antimicrobial activity against one or more of Campylobacter jejuni, Escherichia coli, Listeria monocytogenes, Salmonella enterica and Legionella pneumophila.

16) Use of the disinfectant of any one of the claims 13-15 in purification of air contaminated with a microbe such as a bacterium, preferably in the purification of air by water tank-based air purification.

17) Use of the disinfectant, the sanitizer or the detergent of any one of the claims 13-15 in decontaminating a surface contaminated with a microbe such as a bacterium and/or in preventing a surface from contamination with a microbe such as a bacterium.

18) Use of the disinfectant, the sanitizer or the detergent according to claim 17, wherein the surface is a surface of a body such as a human body, such as the hand of a human subject.

19) Use of the antimicrobial composition according to any one of the claims 1- 12 in decontamination of an aqueous solution such as water contaminated with a microbe such as a bacterium, wherein the antimicrobial composition is added to the aqueous solution at a concentration of at least 0.2% by weight of the antimicrobial composition based on the total weight of the aqueous solution, preferably between 0.3% and 25% by weight, more preferably between 0,5% and 5% by weight, most preferably between 0.7% and 4% by weight, such as 0.75% by weight, 1.5% by weight and 3% by weight, based on the total weight of the aqueous solution.

20) Use according to claim 19, wherein the antimicrobial composition has antimicrobial activity against Legionella pneumophila.