Synergistic antimicrobial compositions comprising a phenolic extract from algae

Abstract

Disclosed are antimicrobial compositions containing a synergistic combination of a phenolic extract from algae and an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, as well as methods of use and product formulations applying the synergistic combinations.

Description

[0001] SYNERGISTIC ANTIMICROBIAL COMPOSITIONS COMPRISING A PHENOLIC EXTRACT FROM ALGAE

[0002] The present invention relates to synergistic antimicrobial compositions, the use of such compositions for killing and / or inhibiting the growth of microorganisms on a substrate or in a product formulation, and product formulations, such as any of personal care, home care, health care, food, and industrial product formulations, containing the synergistic materials of the present disclosure.

[0003] Benzoic acid, salts thereof and other soft preservatives are widely used as antimicrobial agents in a variety of industries, such as in food, personal care (e.g., cosmetic), home care, health care (e.g., pharmaceutical), and industrial product formulations. However, soft preservatives used alone, such as benzoic acid, salts thereof, benzyl alcohol and phenoxyethanol, may not provide broad-spectrum antimicrobial activity necessary for robust protection, potentially complicating their use in product formulations and / or requiring undesirably high dosing levels. There remains a need to address the efficacy gap of soft preservatives, while aligning with increasing consumer demand for natural and sustainable products.

[0004] This need is met by the present disclosure, which is based on the surprising discovery that a combination of a phenolic extract from algae with an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof exhibits synergistic antimicrobial activity against bacteria and fungi. The phenolic extract from algae can therefore synergistically boost or enhance the antimicrobial performance of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof and further allows for dosing lower levels of such materials to achieve desired antimicrobial or preservative effects compared to the use of such materials in the absence of the phenolic extract from algae.

[0005] In one aspect of the present disclosure, an antimicrobial composition comprises an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0006] In a further aspect, the antimicrobial composition is in the form of an aqueous product formulation, such as a product formulation described herein.

[0007] In a further aspect, the antimicrobial composition is in the form of a personal care, home care, health care, food, or industrial product formulation. As used herein, a “food” product formulation shall be understood to include, without limitation, beverage formulations.

[0008] In another aspect, the present disclosure provides an aqueous product formulation, such as a product formulation described herein, comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. Also provided is a personal care, home care, health care, food or industrial product formulation comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0009] In another aspect, a method of providing antimicrobial activity to a substrate or to a product formulation (e.g., killing and / or inhibiting the growth of microorganisms on a substrate or in a product formulation) comprises applying to the substrate or adding to the product formulation (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid, and / or at least one salt thereof, benzyl alcohol, phenoxyethanol, or a combination thereof, and the phenolic extract (a) and the antimicrobial agent (b) are applied or added in an antimicrobial effective amount.

[0010] In a further aspect, the present disclosure includes a method of enhancing the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, the method comprising combining or mixing the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof with a phenolic extract from algae. Also provided is the use of a phenolic extract from algae to enhance the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. As described herein, the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof is synergistically enhanced.

[0011] Additionally provided is a method of reducing the minimum amount of an antimicrobial agent needed for preservation activity in a product formulation, such as a product formulation described herein, the method comprising combining or mixing a phenolic extract from algae with the antimicrobial agent, wherein the antimicrobial agent comprises benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, and wherein after said combination or mixing with the phenolic extract from algae, the minimum amount of the antimicrobial agent needed for preservation activity in the product formulation is less than if the antimicrobial agent was used alone.

[0012] As used herein, an “antimicrobial effective amount” means an amount to provide a desired antimicrobial effect or activity, such as a desired preservative, antibacterial, and / or antifungal effect, in particular killing and / or inhibiting the growth of microorganisms, such as bacteria and fungi. Depending on the context, an “antimicrobial effective amount” may also refer to a concentrated amount in a composition, which can be diluted in use in a product formulation to provide the desired antimicrobial effect or activity for the intended application.

[0013] As used herein, the term “synergistic” and the like mean that the antimicrobial effect (e.g., an antibacterial and / or antifungal effect) of the combination is greater than the additive effect of each component. A synergistic antimicrobial effect can be shown, for example, based on application challenge testing as disclosed herein or based on the calculation of a Synergy Index value, such as determined via Minimum Inhibitory Concentration (MIC) testing or biocidal activity testing as disclosed herein. For example, the Synergy Index may be determined according to the equation: Synergy Index =Ca / CA +Cb / CB, where CA is the concentration (ppm) needed of substance A alone to produce the endpoint, CB is the concentration (ppm) needed of substance B alone to produce the endpoint, Cais the concentration (ppm) of substance A needed when it is used in combination with substance B to produce the endpoint, and Cb is the concentration (ppm) of substance B needed when it is used in combination with substance A to produce the endpoint. As in the Examples of the present disclosure, the endpoint may be inhibition of visible bacterial and / or fungal growth or may be a certain level of viable bacterial or fungal log reduction (e.g., a 99.99% viable bacterial or fungal log reduction) in a given culture medium. A Synergy Index less than one (<1) means synergism exists, a Synergy Index of one (1) means an additive effect exists, and a Synergy Index greater than one (>1) means antagonism exists.

[0014] As used herein, the term “microorganism” includes, for example, bacteria and fungi (such as yeast and mold).

[0015] As used herein, the term “phenolic extract” from algae means that the extract from algae has a phenolic content equivalent to at least 1 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method. Preferably, the extract has a phenolic content equivalent to at least 5 mg or to at least 10 mg phloroglucinol, more preferably equivalent to at least 20 mg or to at least 30 mg of phloroglucinol, most preferably equivalent to at least 40 mg, to at least 50 mg, to at least 60 mg, or to at least 70 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method, which is a known method utilizing the Folin-Ciocalteu reagent for determining phenolic content (Waterhouse, A. L., “Determination of Total Phenolics,” Current Protocols in Food Analytical Chemistry, Vol. 6, 2002). In this method, absorbance at 765 nm is measured and quantified using a phenolic compound as an equivalent. All phenolic contents described herein refer to phenolic content determined according to the “Folin- Ciocalteu method” using phloroglucinol as the equivalent.

[0016] As used herein, “formulation” refers to a preparation that is to be preserved or provided with antimicrobial activity by employing the combination of the phenolic extract from algae (a) and the antimicrobial agent (b) of the present disclosure.

[0017] The antimicrobial compositions, product formulations and methods of the present disclosure are based on the synergistic combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol, or a combination thereof. It was surprisingly discovered that the phenolic extract of the present disclosure can synergistically boost or enhance the antimicrobial efficacy of an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof (e.g., the ability to kill and / or inhibit the growth of microorganisms, thereby synergistically enhancing an antibacterial, antifungal and / or preservation effect). The synergistic antimicrobial effect is preferably against bacteria, particularly, e.g., Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis. Escherichia coli, Enterohacter gergoviae, Klebsiella pneumoniae, Burholderia cepacia, Pseudomonas putida, and mixtures thereof, and fungi, particularly, e.g., Candida albicans, Aspergillus niger and mixtures thereof.

[0018] The phenolic extract from algae of the present disclosure has a phenolic content (minimum) equivalent to at least 1 mg phloroglucinol (i.e., 1 mg or higher phloroglucinol) per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method. Preferably, the phenolic content of the algae is equivalent to at least 5 mg or to at least 10 mg phloroglucinol (i.e., 5 mg or higher or 10 mg or higher phloroglucinol), more preferably equivalent to at least 20 mg or to at least 30 mg phloroglucinol (i.e., 20 mg or higher or 30 mg or higher phloroglucinol), most preferably equivalent to at least 40 mg, to at least 50 mg, to at least 60 mg or to at least 70 mg phloroglucinol (i.e., 40 mg or higher, 50 mg or higher, 60 mg or higher or 70 mg or higher phloroglucinol), per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method. Preferably, the phenolic content in the extract has a phloroglucinol equivalency value ranging from about 5 mg or from about 10 mg to about 100 mg, to about 99 mg, to about 98 mg, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, more preferably ranging from about 20 mg or from about 30 mg to about 100 mg, to about 99 mg, to about 98 mg, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, most preferably ranging from about 40 mg, from about 50 mg, from about 60 mg or from about 70 mg to about 100 mg, to about 99 mg, to about 98, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, determined according to the Folin-Ciocalteu method.

[0019] The algae extract of the present disclosure may be substantially phenolic, that is, the extract may have a phenolic content equivalent to at least 80 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method. In such embodiments, preferably the phenolic content is equivalent to at least 90 or at least 95 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

[0020] The phenolic extract of the present disclosure is preferably an extract from brown algae, red algae and / or green algae, more preferably from brown algae and / or red algae, most preferably from brown algae. Examples of suitable brown algae include, but are not limited to, those of the genera Ascophyllum, Fucus, Ecklonia, Laminaria, Saccharina, Alaria, Cladosiphan, Durvillaea, Lessonia, Macrocystis, Undaria, Pelvetia, Sargassum, Cystoseira, and Padina, preferably of the genera Ascophyllum, Fucus, Ecklonia or Laminaria, most preferably Ascophyllum. Examples of suitable red algae include, but are not limited to, those of the genera Hypnea and Jania. Examples of suitable green algae include, but are not limited to, those of the genus Ulva. The phenolic extract may be derived from a particular species of algae or may be derived from two or more different species of algae, either of the same genus or of different genera. Preferably, the phenolic extract is derived from brown algae, preferably of the genus Ascophyllum. In particular, the phenolic extract may comprise, or consist essentially of, or consist of an extract from the brown algae Ascophyllum nodosum.

[0021] The algae source materials may be obtained from commercial sources or harvested according to known collection procedures. The algae source materials may be in any suitable form for extraction, such as chopped, ground or pulverized form, preferably in the form of a powder. The phenolic extract may be prepared according to extraction procedures as known in the art or later developed, particularly procedures designed to effectively yield polyphenol -rich extracts.

[0022] For example, a phenolic extract from algae, such as the brown algae Ascophyllum, may be prepared by treating the algae source material in a solvent under conditions permitting extraction of phenolic material into the solution. The resulting crude extract may optionally thereafter be purified by any means known in the art, including, for example, centrifugation, precipitation, dialysis, filtration, recrystallization, distillation, adsorption, chromatographic methods, fractionation, etc.

[0023] The extraction solvent is typically a polar solvent, such as a polar solvent miscible with water. Suitable solvents include, for example, water, alcohols (e.g., lower alcohols, such as C1-C4 alcohols, particularly, e.g., ethanol, methanol, 1-propanol, isopropanol), acetone, and aqueous mixtures thereof. Preferably, the extraction solvent may be a water / alcohol solution or water / acetone solution, for example, in a water: alcohol or water: acetone ratio by volume from about 10:90 to about 90: 10. Often, the water / alcohol or water / acetone solution has a wateralcohol or wateracetone ratio of about 80:20, about 70:30, about 60:40, about 50:50, about 40:60, about 30:70, about 20:80, or any range therebetween. For example, typically the water / alcohol or water / acetone solution has a wateralcohol or water / acetone ratio from about 70:30 to about 30:70 or from about 60:40 to about 40:60.

[0024] Preferably, the alcohol is ethanol or methanol.

[0025] Extraction may be performed at temperatures of, for example, at or above about 10 °C, at or above about 20 °C, at or above about 30 °C, at or above about 40 °C, or at or above about 50 °C., and typically less than or equal to about 100 °C, less than or equal to about 90 °C, less than or equal to about 80 °C, less than or equal to about 70 °C or less than or equal to about 60 °C. In many embodiments, such as when extracting with a water / alcohol or water / acetone solution, e.g., a water / ethanol solution, the extraction temperature may range from about 20 °C to about 100 °C, such as from about 20 °C to about 80 °C or from about 25 °C to about 70 °C.

[0026] Examples of suitable extraction times include, without limitation, from about 1, 2, 3 or 4 hours to about 72 hours, from about 1, 2, 3 or 4 hours to about 48 hours, from about 1, 2, 3 or 4 hours to about 36 hours, or from about 1, 2, 3 or 4 hours to about 24 hours. Examples of suitable ratios (v / w) of solvent to algae include, without limitation, from about 2: 1 to about 100: 1, from about 2: 1 to about 50: 1 or from about 2: 1 to about 30: 1, such as from about 4: 1 to about 20: 1.

[0027] The extraction may be performed under agitation, for example by agitating the extraction vessel, by mechanical stirring, or through the action of heating, and optionally under reflux.

[0028] The crude extract is typically concentrated through removal of organic solvent, such as by a vacuum method, e.g. rotary evaporation, and dried, e.g., freeze-dried, lyophilized, or spray-dried, to yield a solid, e.g., powdered, crude extract.

[0029] The crude extract may be purified, either before or after concentration and drying, by any means known in the art, such as centrifugation, precipitation, dialysis, filtration, re -crystallization, distillation, adsorption, chromatographic methods, fractionation, etc. A combination of techniques may be used.

[0030] The antimicrobial agent (b) of the present disclosure comprises benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. Examples of suitable salts of benzoic acid include, but are not limited to, sodium benzoate, potassium benzoate, calcium benzoate, magnesium benzoate, zinc benzoate, and ammonium benzoate. One or more than one salt of benzoic acid may be used. Preferably, the at least one benzoic acid salt is sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably, sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate.

[0031] The antimicrobial agent (b) may further include at least one additional antimicrobial or preservative material, such as those suitable for use in a personal care, home care, health care, food or industrial product. Examples include, without limitation, propionic acid, salicylic acid, sorbic acid, lactic acid, acetic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, salts thereof (such as salts of sodium, potassium, calcium, magnesium or ammonium, particularly salts of sodium or potassium, e.g., potassium sorbate or sodium sorbate), esters thereof (particularly esters of 4- hydroxybenzoic acid, such as those of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, e.g., methylparaben, ethylparaben, propylparaben, butylparaben, etc.), dichlorobenzyl alcohol, phenethyl alcohol, hydroxyacetophenone, ethylhexylglycerin, chlorphenesin, pyrithiones (e.g., zinc pyrithione and / or sodium pyrithione), isothiazolinones (e.g., 5 -chloro-2 -methyl -4-isothiazolin-3 -one (CMIT), 2- methyl-4-isothiazolin-3-one (MIT), l,2-benzisothiazolin-3-one (BIT) and combinations thereof), ethyl lauroyl arginate (LAE) and combinations of the foregoing. Preferably, at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt% or at least 40 wt% of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. Typically, at least a majority by weight of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, such as at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, or all or substantially all of the antimicrobial agent (b) is benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. The antimicrobial agent (b) may consist essentially of, or in further embodiments consist of, benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof. The antimicrobial agent (b) may consist essentially of or consist of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof and at least one additional antimicrobial or preservative material, such as at least one preservative material chosen from, salicylic acid, sorbic acid, lactic acid, acetic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, salts thereof (such as salts of sodium, potassium, calcium, magnesium or ammonium, particularly salts of sodium or potassium, e.g., potassium sorbate or sodium sorbate), esters thereof (particularly esters of 4-hydroxybenzoic acid, such as those of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, e.g., methylparaben, ethylparaben, propylparaben, butylparaben, etc.), dichlorobenzyl alcohol, phenethyl alcohol, hydroxyacetophenone, ethylhexylglycerin, chlorphene sin, pyrithiones (e.g., zinc pyrithione and / or sodium pyrithione), isothiazolinones (e.g., 5 -chloro-2 -methyl -4-isothiazolin-3 -one (CMIT), 2-methyl- 4-isothiazolin-3-one (MIT), l,2-benzisothiazolin-3-one (BIT), combinations thereof), ethyl lauroyl arginate (LAE) and combinations of the foregoing.

[0032] The antimicrobial composition may include a solvent or carrier component (c). The solvents or carriers may be chosen, for example, according to their suitability for the intended end-use application, such as for an intended product formulation. For instance, the solvents or carriers may be cosmetically acceptable solvents or carriers, pharmaceutically acceptable solvents or carriers, or food acceptable solvents or carriers. Examples of suitable solvents or carriers are water and water miscible solvents or carriers, including, but not limited to, alcohols (e.g., lower alcohols (such as C1-C4 alcohols), such as methanol, ethanol, propanol, iso-propanol, and butanol), diols (e.g., lower diols (such as C1-C4 diols and glycols) and other glycols, such as dipropylene glycol and butoxydiglycol), glycerin, diglycerin, esters, ethers, polyethers, and combinations thereof. For example, the solvent or carrier may comprise water and one or more glycols, glycerin, and / or one or more alcohols.

[0033] The phenolic extract from algae (a) and the antimicrobial agent (b) may be in any suitable form for preparing the antimicrobial composition and may be combined in any suitable manner. For example, either or both may be in solid form or may be in a solvent or carrier. As described above, the solvents or carriers may be chosen to ensure compatibility with a desired product formulation and / or intended end-use application.

[0034] As described herein, the antimicrobial activity (e.g., an antibacterial and / or antifungal effect) of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof is synergistically enhanced against various microorganisms, including bacteria and fungi (yeast and mold), when combined with the phenolic extract from algae of the present disclosure. For example, the presently disclosed combinations preferably kill and / or inhibit the growth of gram positive bacteria, gram negative bacteria, and fungi. Non-limiting examples include Staphylococcus aureus, Staphylococcus epidermidis. Pseudomonas aeruginosa, Escherichia coli, Enterohacter gergoviae, Klebsiella pneumoniae, Burkholderia cepacia, Pseudomonas putida, Candida albicans, Aspergillus niger, and mixtures thereof.

[0035] Optimized ratios by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract from algae for optimizing the synergistic combination may vary depending, for example, on the particular combination selected, the end use application, the final properties of the product, and the like. Preferably, in the compositions, formulations and methods of the present disclosure, the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract from algae ranges from about 100: 1 or from about 50: 1 to about 1:500, more preferably from about 100: 1 or from about 50 : 1 to about 1 : 200 or to about 1 : 100 or from about 25 : 1 to about 1: 100, particularly from about 20: 1 to about 1:50 or from about 15: 1 to about 1:25, most preferably from about 10: l to about 1:20, from about 10: l to about 1: 15, from about 5: 1 to about 1: 15, or from about 10: 1, from about 5: 1, from about 3: 1, from about 2: 1 or from about 1: 1 to about 1: 15, to about 1: 10 or to about 1:5.

[0036] In particular, without wishing to be bound by a particular theory, it is believed that the synergistic antimicrobial enhancement relates to the presence of the phenolic compounds in the phenolic extract. The amount of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof relative to the phenolic extract can be particularly expressed according to the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method. The ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract preferably ranges from about 100: 1 or from about 50: 1 to about 1 :500, more preferably from about 100: 1 or from about 50: 1 to about 1 :200 or to about 1 : 100 or from about 25: 1 to about 1: 100, particularly from about 20: 1 to about 1:50 or from about 15: 1 to about 1:25, most preferably from about 10: 1 to about 1:20, from about 10: 1 to about 1: 15, from about 5 : 1 to about 1 : 15 , or from about 10: 1, from about 5: 1, from about 3: 1, from about 2 : 1 or from about 1 : 1 to about 1 : 15 , to about 1 : 10 or to about 1:5. It shall be understood that the amount of the phenolic extract necessary to realize such ratios is dependent upon the phenolic concentration in the phenolic extract, which, in accordance with the present disclosure, can be determined according to the Folin- Ciocalteu method. The antimicrobial composition can comprise a concentrated mixture of the phenolic extract from algae (a) and the antimicrobial agent (b). In such embodiments, the antimicrobial effective amount is a concentrated amount, which can be diluted in a product or end-use formulation to provide the desired antimicrobial effect or activity for the intended application. In such concentrated embodiments, the combination of (a) and (b) preferably constitutes 50 to 100 wt% of the active ingredients in the antimicrobial composition, typically a majority (>50 wt%) of the active ingredients, such as at least 60 wt% or at least 70 wt%, preferably at least 80 wt%, more preferably at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at least 98 wt% or at least 99 wt%, based on the total weight of active ingredients in the antimicrobial composition. The concentrated antimicrobial composition may contain, for example, from about 60 to 100 wt%, preferably from about 65 to 100 wt%, from about 70 to 100 wt%, from about 75 to 100 wt%, from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or from about 97 to 100 wt%, of the phenolic extract from algae (a) and the antimicrobial agent (b) combined, based on the total weight of active ingredients in the antimicrobial composition. In many embodiments, the concentrated antimicrobial composition comprises active ingredients consisting essentially of, or in further embodiments consisting of, the components (a) and (b).

[0037] The concentrated antimicrobial composition of the present disclosure may comprise a solvent or carrier (c), such as described above. If present, the solvent or carrier (c) typically constitutes from about 10 wt%, from about 20 wt% or from about 30 wt% to about 95 wt%, to about 90 wt%, to about 85 wt%, to about 80 wt%, to about 70 wt%, to about 60 wt% or to about 50 wt%, based on the total weight of the concentrated antimicrobial composition.

[0038] The concentrated antimicrobial composition may contain one or more excipients (d), typically in minor quantities. Excipients may be chosen, for example, according to their suitability for the intended end-use application or product formulation, e.g., in a personal care formulation (e.g., a cosmetically acceptable excipient) or in a health care formulation (e.g., a pharmaceutically acceptable excipient) or in a food product formulation (e.g., a food acceptable excipient). Examples of excipients include, but are not limited to, a dispersant, solubilizer, buffer, and / or stabilizer. The concentrated antimicrobial composition may comprise one or more excipients (d), for example, from 0 to about 10 wt%, such as from about 0.001 wt%, from about 0.01 wt%, from about 0.05 wt% or from about 0. 1 wt% to about 10 wt%, to about 5 wt%, to about 3 wt%, or to about 1 wt%, based on the total weight of the concentrated antimicrobial composition. For example, the component (d) may range from 0 to about 5 wt%, from 0 to about 3 wt% from about 0.01 to about 5 wt%, from about 0. 1 to about 5 wt%, from about 0.01 to about 3 wt%, from about 0. 1 to about 3 wt%, from about 0.01 to about 1 wt%, or from about 0.1 to about 1 wt%.

[0039] In general, the concentrated antimicrobial composition may comprise a combined amount of the phenolic extract from algae (a) and the antimicrobial agent (b) of from about 1 to 100 wt%, preferably from about 5 wt%, from about 10 wt%, from about 15 wt%, from about 20 wt%, from about 30 wt%, from about 40 wt%, from about 50 wt% or from about 60 wt% to about 100 wt%, to about 99 wt%, to about 97 wt%, to about 95 wt%, to about 90 wt%, to about 80 wt%, or to about 70 wt%, based on the total weight of the concentrated antimicrobial composition; optionally one or more solvents or carriers (c) in an amount from 0 to about 99 wt%, such as from about 10 wt%, from about 20 wt% or from about 30 wt% to about 95 wt%, to about 85 wt%, to about 80 wt%, to about 70 wt%, to about 60 wt%, to about 50 wt%, or to about 40 wt%, based on the total weight of the concentrated antimicrobial composition; and optionally one or more excipients (d) in an amount from about 0 to about 10 wt%, such as from about 0.001 wt%, from about 0.01 wt%, from about 0.05 wt% or from about 0.1 wt% to about 10 wt%, to about 5 wt%, to about 3 wt%, or to about 1 wt%, based on the total weight of the concentrated antimicrobial composition. For example, the combined amount of (a) and (b) may be from about 1 wt% to about 99 wt%, from about 5 wt% to about 95 wt%, from about 10 wt% to about 90 wt%, from about 20 wt% to about 80 wt%, or from about 30 wt% to about 70 wt%, and the amount of solvent or carrier (c) may be from about 1 wt% to about 99 wt%, from about 5 wt% to about 95 wt%, from about 10 wt% to about 90 wt%, from about 20 wt% to about 80 wt%, or from about 30 wt% to about 70 wt%, optionally further comprising component (d).

[0040] In many embodiments, the concentrated antimicrobial composition consists essentially of, or in further embodiments consists of, the phenolic extract from algae (a), the antimicrobial agent (b), optionally one or more solvents or carriers (c), and optionally one or more excipients (d).

[0041] The present disclosure is not limited to any particular technique for preparing the concentrated antimicrobial composition and such composition may be prepared in any suitable manner for combining or mixing the components described herein.

[0042] In another aspect of the present disclosure, the antimicrobial composition is in the form of a product formulation, especially aqueous product formulations. An aqueous product formulation in this context refers to formulations that include water, such as a solvent or carrier, in the formulation medium or media, such as those in the form of a liquid, solution, lotion, cream, gel, dispersion, suspension, emulsion or microemulsion (e.g., oil-in-water emulsions, water-in-oil emulsions, silicone- in-water emulsions, water-in-silicone emulsions, etc.).

[0043] Preferably, the antimicrobial composition is in the form of a personal care (e.g., cosmetic), home care, health care (e.g., pharmaceutical (i.e., having at least one active pharmaceutical ingredient), vitamin, nutraceutical or other health care products), food, or industrial product formulation. Examples include, without limitation, household products and cleaners, fabric detergents, dish detergents, cleansers, soaps, bubble baths, disinfectants, deodorizers, food products (including beverages), antimicrobial packaging, pharmaceutical products, medical device products, contact lens products, cosmetics, hygiene compositions, infant care products, antimicrobial soaps, hand sanitizers, deodorants, antiperspirants, dental compositions, toothpastes, mouthwashes, lipsticks, dental appliances, medications, athlete's foot treatments, medicated chewing gums, wound care compositions, dermatological compositions, acne treatments, skin conditioners, skin moisturizers, anti-wrinkle formulations, skin whiteners, sunscreens, lotions, hair products, shampoos, shower gels, bubble baths, conditioners, wipes, creams, paints, coatings, adhesives, agricultural products, etc. Also included are formulations for providing microbial-resistance to fabrics and apparel, condoms, surgical gowns, hospital equipment, paper products, animal care products, plastics, rubbers or other fabrication materials, appliances with antimicrobial constituents or coatings, etc. Depending on the application, the product formulation may contain numerous and different compatible ingredients. For example, the product formulation may comprise an antimicrobial effective amount of the combination of the phenolic extract from algae (a) and the antimicrobial agent (b) and one or more additional ingredients suitable for use in a personal care (e.g., cosmetic), home care, health care (e.g., pharmaceutical, vitamin, nutraceutical or other health care products), food or industrial product formulation.

[0044] As a particular example, the antimicrobial composition is in the form of a personal care product formulation, such as a cosmetic product. The personal care formulation comprises an antimicrobial effective amount of a combination of the phenolic extract from algae (a) and the antimicrobial agent (b) and one or more additional ingredients suitable for use in a personal care formulation. The personal care formulation may be, for example, any formulation for skin care, hair care, cosmetics, personal cleaning, hygiene, sun protection and other personal care applications. Examples of such products include, without limitation, skin toners, skin cleansers, night creams, skin creams, shaving creams, skin lotions, makeup, mascara, lipstick, blush, gloss, eye-liner, makeup removers, sunscreens, lip balms, fragrances, massage oils, shampoos, conditioners, hair styling gels, hair reparatives, hair tonics, hair fixatives, hair mousses, bath and shower gels, liquid soaps, moisturizing sprays, bath additives, ophthalmic preparations, foaming soaps and body washes, liquids for any personal care wet wipe application, etc.

[0045] Depending on the application, the personal care product formulation may contain numerous and different compatible ingredients. A personal care formulation may contain, for example, any of solvents, surfactants, emulsifiers, chelating agents, oxidizing agents, gelling agents, colorants, rheology modifiers, conditioners, emollients, skin care or protection ingredients, moisturizers, thickeners, humectants, fillers, antioxidants, active ingredients, such as dermatologically active ingredients typically suited for topical application, fragrances, etc.

[0046] As a further example, the antimicrobial composition is in the form of a home care product formulation, such as fabric care products or cleaning products. The home care formulation comprises an antimicrobial effective amount of a combination of the phenolic extract from algae (a) and the antimicrobial agent (b) and one or more additional ingredients suitable for use in a home care formulation. Examples include dish soaps, laundry detergents, cleaning wipes, cleaning formulations and other home care applications.

[0047] Depending on the application, the home care product formulation may contain, for example, any of cleaning agents, detergents, emulsifiers, surfactants, thickeners, gelling agents, bleaches, whiteners, deodorizers, enzymes, stabilizers, fragrances, soil-release agents, anti-shrinking agents, anti-wrinkle agents, anti-spotting agents, antioxidants, UV absorbing compounds, anti -corrosion agents, anti-static agents, ironing aids, odor-preventing compounds, etc.

[0048] Examples of the foregoing ingredients and other agents used in personal care and home care product formulations are known in the art.

[0049] The antimicrobial composition may be in the form of an industrial product formulation. The industrial product formulation comprises an antimicrobial effective amount of a combination of the phenolic extract from algae (a) and the antimicrobial agent (b) and one or more additional ingredients suitable for use in an industrial product formulation, such as one or more ingredients suitable for use in formulations in the form of paints, coatings, varnishes, stains, wood products, liquids associated with textile production, adhesives, sealants, liquids associated with leather making, ropes, liquids associated with paper processing, pulps, paper boards, sheet rocks, ceiling tiles, plastics, fuels, petroleum, oils, rubber working fluids, metal working fluids, starches, chalk slurries, mineral slurries, and other industrial applications.

[0050] The antimicrobial composition may be in the form of a food product formulation, such as beverages, canned or processed foods, condiments, sauces, fruit preserves, candies, etc. The food product formulation comprises an antimicrobial effective amount of a combination of the phenolic extract from algae (a) and the antimicrobial agent (b) (preferably comprising benzoic acid and / or at least one salt thereof, such as sodium benzoate and / or potassium benzoate) and one or more additional ingredients suitable for use in a food product formulation. Depending on the product, the food product formulation may contain, for example, any of water and / or other liquids, sweeteners, flavoring agents, coloring agents, stabilizers, emulsifiers, syrups, nutritional ingredients, etc.

[0051] The antimicrobial composition may be in the form of a health care product formulation, such as a pharmaceutical, vitamin, nutraceutical or other health care product formulation. The health care product formulation comprises an antimicrobial effective amount of a combination of the phenolic extract from algae (a) and the antimicrobial agent (b) and one or more additional ingredients suitable for use in a health care product formulation. Examples include formulations or dosages in liquid, gel, cream, ointment, semi-solid, topical, injectable, spray, drop and other forms.

[0052] Depending on the application, the health care product formulation may contain, for example, any of solvents, emulsifiers, surfactants, antioxidants, buffers, gelling agents, chelating agents, colorants, flavoring agents, fragrances, emollients, humectants, thickeners, active pharmaceutical ingredients, nutritional ingredients, etc.

[0053] Typically, the product formulations have a pH ranging from about 3.0, from about 4.0, from about 5.0, from about 5.5, or from about 6.0 to about 11, such as from about 3.0 to about 10, preferably from about 4.0 to about 8.5, or more preferably from about 5.0 to about 7.5. Unless otherwise specified, pH values or ranges refer to pH at room temperature (20-25 °C). The selected pH will vary depending, for example, on the particular end use application. For example, the personal care product formulations preferably have a pH ranging from about 3.0 or from about 4.0 to about 8.0, such as from about 4.0 or from about 5.0 to about 7.5 or to about 7.0. The home care product formulations preferably have a pH ranging from about 3.0 to about 11, such as from about 4.0 or from about 5.0 to about 10, or from about 5.0 or from about 6.0 to about 9.0, to about 8.0, to about 7.5 or to about 7.0.

[0054] The phenolic extract from algae (a) and the antimicrobial agent (b) of the present disclosure may be included in product formulations of a variety of different forms, for example, liquids, pastes, serums, hydrogels, creams, emulsions, lotions, gels, oils, wipes, ointments, semi-solid compositions, foams and aerosol sprays. They may be used in a leave-on or rinse-off product formulation. Examples include hair care products, such as shampoos, hair conditioners, hair dyes, hair tonic, hair gel, hair dressings, hair grooming aids and other hair care preparations; shaving applications such as shaving cream, aftershave lotions, and other shaving applications; personal cleaners for the body and hands, such as liquid bath soaps and detergents; fragrance preparations, such as perfumes, after bath splashes, and other similar fragrant preparations, skin care products, such as moisturizers, creams, and lotions and other similar skin care products, make-up products, such as mascara, base foundations and the like; make-up removal products, sun care products, indoor tanning products and other similar personal care products. The phenolic extract from algae (a) and the antimicrobial agent (b) may be incorporated in formulations used to saturate wipes used for personal cleaning and hygiene, for example baby wipes, wet toilet wipes, make-up removal wipes and exfoliating wipes the like, or wet wipe formulations for home care.

[0055] An optimized antimicrobial effective amount of the combination of the phenolic extract from algae (a) and the antimicrobial agent (b) in a product formulation may vary depending, for example, on the particular combination selected, the end use application, the desired level of antimicrobial activity, the final properties of the product, and the like. Typically, the antimicrobial effective amount of the combination of the phenolic extract from algae (a) and the antimicrobial agent (b) ranges from about 0.005 wt%, from about 0.01, or from about 0.05, more preferably from about 0.1 wt%, from about 0.3 wt% or from about 0.5 wt% to about 20 wt% or to about 15 wt%, preferably to about 10 wt%, to about 5 wt%, or to about 4 wt%, more preferably to about 3.5 wt%, to about 3 wt%, to about 2 wt%, or to about 1 wt%, based on the total weight of the product formulation. For example, the combined antimicrobial effective amount may be from about 0.05 to about 7 wt%, such as from about 0.1 to about 5 wt%, preferably from about 0.2 to about 4 wt%, or from about 0.2, from about 0.3 or from about 0.5 to about 4, to about 3.5 or to about 3 wt%, based on the total weight of the product formulation.

[0056] Preferably, the antimicrobial agent (b) is present in the product formulation in an amount not exceeding 3 wt%, not exceeding 2 wt%, or not exceeding 1 wt%, based on the total weight of the product formulation. Preferably, the combined antimicrobial effective amount of the components (a) and (b) does not exceed 5 wt%, preferably not exceeding 4 wt%, 3.5 wt% or 3 wt%, based on the total weight of the product formulation. More preferably, the product formulation comprises no greater than 1.5 wt%, particularly no greater than 1 wt%, no greater than 0.9 wt%, no greater than 0.8 wt%, no greater than 0.7 wt%, no greater than 0.6 wt%, no greater than 0.5 wt%, no greater than 0.4 wt% or no greater than 0.3 wt% of the antimicrobial agent (b).

[0057] The present disclosure is not limited to any particular technique for preparing the product formulations. The phenolic extract from algae (a) and the antimicrobial agent (b) of the present disclosure may be applied to a substrate or added to a product formulation in any suitable manner. For example, the phenolic extract from algae (a), the antimicrobial agent (b), and the other ingredients as described herein can be added to a product formulation as a mixture or applied individually to the formulation at the same time or in any order. The product formulations to which the phenolic extract (a) and the antimicrobial agent (b) are added may, but need not, contain other antimicrobial or preservative materials.

[0058] In another aspect, a method of providing antimicrobial activity to a substrate or to a product formulation (e.g., killing and / or inhibiting the growth of microorganisms on a substrate or in a product formulation), such as a product formulation described herein, comprises applying to the substrate or adding to the product formulation the phenolic extract from algae (a) and the antimicrobial agent (b), and the components (a) and (b) are applied or added in an antimicrobial effective amount. The substrate may be, for example, wood, plastic, metal, or non-metal surfaces, textiles, fabrics, etc.

[0059] In a further aspect, a method of synergistically enhancing the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof comprises combining or mixing the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof with the phenolic extract from algae. Also provided is the use of the phenolic extract from algae to synergistically enhance the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0060] Additionally provided is a method of reducing the minimum amount of the antimicrobial agent needed for preservation activity in a product formulation, such as a product formulation described herein, the method comprising combining or mixing the phenolic extract from algae with the antimicrobial agent. After said combination or mixing with the phenolic extract, the minimum amount of the antimicrobial agent needed for preservation activity in the product formulation is less than if the antimicrobial agent was used alone.

[0061] It shall be understood that the descriptions herein with respect to the phenolic extract from algae (a), the antimicrobial agent (b), exemplary ratios and amounts, product formulations and ingredients, etc. also apply to the methods of the present disclosure.

[0062] The present disclosure further includes, without limitation, the following exemplary embodiments.

[0063] Embodiment 1 : An antimicrobial composition comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising, or consisting essentially of or consisting of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0064] Embodiment 2: The antimicrobial composition according to Embodiment 1, wherein the phenolic extract comprises, or consists essentially of, or consists of at least one extract derived from brown algae.

[0065] Embodiment 3 : The antimicrobial composition according to Embodiment 2, wherein the brown algae is of the genera Ascophyllum. preferably the species Ascophyllum nodosum.

[0066] Embodiment 4: The antimicrobial composition according to any preceding Embodiment, wherein the antimicrobial agent comprises, or consists essentially of or consists of benzoic acid and / or at least one salt thereof.

[0067] Embodiment 5: The antimicrobial composition according to any one of Embodiments 1-3, wherein the antimicrobial agent comprises, or consists essentially of or consists of benzyl alcohol.

[0068] Embodiment 6: The antimicrobial composition according to any one of Embodiments 1-3, wherein the antimicrobial agent comprises, or consists essentially of or consists of phenoxyethanol.

[0069] Embodiment 7: The antimicrobial composition according to any one of Embodiments 1-3, wherein the antimicrobial agent comprises, or consists essentially of or consists of a combination of two or more of benzoic acid and / or at least one salt thereof, benzyl alcohol and phenoxyethanol.

[0070] Embodiment 8: The antimicrobial composition according to any one of Embodiments 1-4 and 7, wherein the antimicrobial agent comprises, or consists essentially of, or consists of at least one salt of benzoic acid, preferably sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate.

[0071] Embodiment 9: The antimicrobial composition according to any preceding Embodiment, wherein the phenolic extract has a phenolic content equivalent to at least 5 mg or to at least 10 mg phloroglucinol, more preferably equivalent to at least 20 mg or to at least 30 mg phloroglucinol, most preferably equivalent to at least 40 mg, to at least 50 mg, to at least 60 mg or to at least 70 mg phloroglucinol, per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

[0072] Embodiment 10: The antimicrobial composition according to Embodiment 9, wherein the phenolic extract has a phenolic content equivalent to from about 5 mg or from about 10 mg to about 100 mg, to about 99 mg, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, more preferably from about 20 mg or from about 30 mg to about 100 mg, to about 99 mg, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, most preferably from about 40 mg, from about 50 mg, from about 60 mg or from about 70 mg to about 100 mg, to about 99 mg, to about 95 mg or to about 90 mg phloroglucinol per 100 mg of extract on a dry weight basis, determined according to the Folin-Ciocalteu method.

[0073] Embodiment 11 : The antimicrobial composition according to any preceding Embodiment, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract ranges from about 100: 1 or from about 50: 1 to about 1:500, more preferably from about 100: 1 or from about 50 : 1 to about 1 : 200 or to about 1 : 100 or from about 25: 1 to about 1: 100, particularly from about 20: 1 to about 1:50 or from about 15: 1 to about 1:25, most preferably from about 10: 1 to about 1:20, from about 10: 1 to about 1: 15, from about 5: 1 to about 1 : 15 , or from about 10: 1, from about 5: 1, from about 3: 1, from about 2 : 1 or from about 1 : 1 to about 1: 15, to about 1: 10 orto about 1:5.

[0074] Embodiment 12: The antimicrobial composition according to any one of Embodiments 1-10, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract ranges from about 100: 1 or from about 50: 1 to about 1:500, more preferably from about 100: 1 or from about 50: 1 to about 1:200 or to about 1 : 100 or from about 25: 1 to about 1 : 100, particularly from about 20: 1 to about 1:50 or from about 15: 1 to about 1:25, most preferably from about 10: 1 to about 1:20, from about 10: 1 to about 1: 15, from about 5 : 1 to about 1 : 15 , or from about 10: 1, from about 5: 1, from about 3: 1, from about 2 : 1 or from about 1 : 1 to about 1 : 15 , to about 1 : 10 or to about 1:5, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

[0075] Embodiment 13: The antimicrobial composition according to any preceding Embodiment, wherein the antimicrobial agent (b) further comprises at least one additional antimicrobial or preservative material, such as those suitable for use in a personal care, home care, health care, food or industrial product.

[0076] Embodiment 14: The antimicrobial composition according to Embodiment 13, wherein at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt% or at least 40 wt% of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, preferably wherein at least a majority by weight of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, such as at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, or all or substantially all of the antimicrobial agent (b) is benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0077] Embodiment 15: The antimicrobial composition according to Embodiment 13 or 14, wherein the at least one additional antimicrobial or preservative material is chosen from salicylic acid, sorbic acid, lactic acid, acetic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, salts thereof (such as salts of sodium, potassium, calcium, magnesium or ammonium, particularly salts of sodium or potassium, e.g., potassium sorbate or sodium sorbate), esters of 4-hydroxybenzoic acid (such as those of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, e.g., methylparaben, ethylparaben, propylparaben, butylparaben, etc.), dichlorobenzyl alcohol, phenethyl alcohol, hydroxyacetophenone, ethylhexylglycerin, chlorphene sin, pyrithiones (e.g., zinc pyrithione and / or sodium pyrithione), isothiazolinones (e.g., 5 -chloro-2 -methyl -4-isothiazolin-3 -one (CMIT), 2-methyl- 4-isothiazolin-3-one (MIT), l,2-benzisothiazolin-3-one (BIT), combinations thereof), ethyl lauroyl arginate (LAE) and combinations of the foregoing.

[0078] Embodiment 16: The antimicrobial composition according to any one of Embodiments 13-15, wherein the antimicrobial agent (b) consists essentially of, or consists of, benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof and the at least one additional antimicrobial or preservative material.

[0079] Embodiment 17: The antimicrobial composition according to any preceding Embodiment, wherein the composition is in a concentrated form comprising from 50 to 100 wt% of the phenolic extract (a) and the antimicrobial agent (b) combined, based on the total weight of active ingredients in the antimicrobial composition, preferably a majority (>50 wt%) of the active ingredients, such as at least 60 wt% or at least 70 wt%, preferably at least 80 wt%, more preferably at least 85 wt%, at least 90 wt%, at least 95 wt%, at least 96 wt%, at least 97 wt%, at least 98 wt% or at least 99 wt%, based on the total weight of active ingredients in the antimicrobial composition.

[0080] Embodiment 18: The antimicrobial composition according to Embodiment 17, wherein the composition comprises from about 60 to 100 wt%, preferably from about 65 to 100 wt%, from about 70 to 100 wt%, or from about 75 to 100 wt%, more preferably from about 80 to 100 wt%, from about 85 to 100 wt%, from about 90 to 100 wt%, or from about 95 or from about 97 to 100 wt%, of the phenolic extract (a) and the antimicrobial agent (b) combined, based on the total weight of active ingredients in the antimicrobial composition.

[0081] Embodiment 19: The antimicrobial composition according to Embodiment 17 or 18, wherein the composition comprises active ingredients consisting essentially of, or consisting of, the phenolic extract (a) and the antimicrobial agent (b). Embodiment 20: The antimicrobial composition according to any one of Embodiments 17-19, further comprising one or more solvents or carriers (c), preferably in an amount ranging from about 10 to about 95 wt% based on the total weight of the composition, such as from about 10 wt%, from about 20 wt% or from about 30 wt% to about 90 wt%, to about 80 wt%, to about 70 wt%, to about 60 wt% or to about 50 wt%, based on the total weight of the composition, preferably wherein the one or more solvents or carriers comprise water, one or more water miscible materials or a combination thereof.

[0082] Embodiment 21: The antimicrobial composition according to any one of Embodiments 17-20, further comprising one or more excipients (d), preferably in an amount ranging from about 0.001 wt%, from about 0.01 wt%, from about 0.05 wt% or from about 0.1 wt% to about 10 wt%, to about 5 wt%, to about 3 wt%, or to about 1 wt%, based on the total weight of the concentrated antimicrobial composition.

[0083] Embodiment 22: The antimicrobial composition according to any one of Embodiments 17-19, wherein the antimicrobial composition consists essentially of, or consists of, the phenolic extract (a), the antimicrobial agent (b), optionally one or more solvents or carriers (c), and optionally one or more excipients (d).

[0084] Embodiment 23: The antimicrobial composition according to any one of Embodiments 1-16, wherein the antimicrobial composition is in the form of an aqueous product formulation, preferably a personal care, home care, health care, food or industrial product formulation.

[0085] Embodiment 24: The antimicrobial composition according to Embodiment 23, wherein the antimicrobial composition is in the form of a personal care, home care or health care product formulation.

[0086] Embodiment 25: The antimicrobial composition according to any one of Embodiments 1-4 and 8-16, wherein the antimicrobial composition is in the form of a food product formulation, and the antimicrobial agent comprises, or consists essentially of, or consists of benzoic acid and / or at least one salt thereof.

[0087] Embodiment 26: The antimicrobial composition according to Embodiment 25, wherein the antimicrobial agent comprises, or consists essentially of, or consists of at least one salt of benzoic acid, preferably sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate.

[0088] Embodiment 27: The antimicrobial composition according to any one of Embodiments 23-26, wherein the antimicrobial effective amount of the combination of the phenolic extract (a) and the antimicrobial agent (b) ranges from about 0.005 wt%, from about 0.01, or from about 0.05, more preferably from about 0.1 wt%, from about 0.3 wt% or from about 0.5 wt% to about 20 wt% or to about 15 wt%, preferably to about 10 wt%, to about 5 wt%, or to about 4 wt%, more preferably to about 3.5 wt%, to about 3 wt%, to about 2 wt%, or to about 1 wt%, based on the total weight of the product formulation, for example, the antimicrobial effective amount of the combination is from about 0.05 to about 7 wt% or from about 0.1 to about 5 wt%, preferably from about 0.2 to about 4 wt%, particularly from about 0.2, from about 0.3 or from about 0.5 to about 4, to about 3.5 or to about 3 wt%, based on the total weight of the product formulation.

[0089] Embodiment 28: A personal care, home care, health care or industrial product formulation comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, such as described in any one or more of Embodiments 2, 3, 9, and 10 above, and (b) an antimicrobial agent comprising, or consisting essentially of, or consisting of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, such as described in any one or more of Embodiments 4-8 and 13-16 above.

[0090] Embodiment 29: The personal care, home care, health care or industrial product formulation according to Embodiment 28, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract is as described in Embodiment 11 above.

[0091] Embodiment 30: The personal care, home care, health care or industrial product formulation according to Embodiment 28, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract is as described in Embodiment 12 above.

[0092] Embodiment 31 : The personal care, home care, health care or industrial product formulation according to any one of Embodiments 28-30, wherein the antimicrobial effective amount of the combination is as described in Embodiment 27 above.

[0093] Embodiment 32: A food product formulation comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, such as described in any one or more of Embodiments 2, 3, 9, and 10 above, and (b) an antimicrobial agent comprising, or consisting essentially of, or consisting of benzoic acid and / or at least one salt thereof.

[0094] Embodiment 33: The food product formulation according to Embodiment 32, wherein the antimicrobial agent comprises, or consists essentially of or consists of at least one salt of benzoic acid, preferably sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate. Embodiment 34: The food product formulation according to Embodiment 32 or 33, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof to the phenolic extract is as described in Embodiment 11 above.

[0095] Embodiment 35: The food product formulation according to any Embodiment 32 or 33, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof to the total phenolic weight of the phenolic extract is as described in Embodiment 12 above.

[0096] Embodiment 36: The food product formulation according to any one of Embodiments 32-35, wherein the antimicrobial effective amount of the combination is as described in Embodiment 27 above.

[0097] Embodiment 37: A method of killing or inhibiting the growth of microorganisms on a substrate or in a product formulation, comprising applying to the substrate or adding to the product formulation (a) a phenolic extract from algae, such as described in any one or more of Embodiments 2, 3, 9, and 10 above, and (b) an antimicrobial agent comprising, consisting essentially of, or consisting of benzoic acid, and / or at least one salt thereof, benzyl alcohol, phenoxyethanol, or a combination thereof, such as described in any one or more of Embodiments 4-8 and 13-16 above, and the phenolic extract (a) and the antimicrobial agent (b) are applied or added in an antimicrobial effective amount.

[0098] Embodiment 38: The method according to Embodiment 37, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract is as described in Embodiment 11 above.

[0099] Embodiment 39: The method according to Embodiment 37, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract is as described in Embodiment 12 above.

[0100] Embodiment 40: The method according to any one of Embodiments 37-39, wherein the antimicrobial effective amount is as described in Embodiment 27 above.

[0101] Embodiment 41: The method according to any one of Embodiments 37-40, wherein the product formulation is a personal care, home care or health care product formulation.

[0102] Embodiment 42: The method according to any one of Embodiments 37-40, wherein the product formulation is an industrial product formulation.

[0103] Embodiment 43: The method according to any one of Embodiments 37-40, wherein the product formulation is a food product formulation, and the antimicrobial agent comprises, or consists essentially of, or consists of benzoic acid and / or at least one salt thereof.

[0104] Embodiment 44: The method according to Embodiment 43, wherein the antimicrobial agent comprises, or consists essentially of, or consists of at least one salt of benzoic acid, preferably sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate.

[0105] Embodiment 45: The product formulation or method according to any one of Embodiments 28-44, wherein the antimicrobial agent (b) further comprises at least one additional antimicrobial or preservative material, such as those suitable for use in a personal care, home care, health care, food or industrial product.

[0106] Embodiment 46: The product formulation or method according to Embodiment 45, wherein at least 5 wt%, at least 10 wt%, at least 20 wt%, at least 30 wt% or at least 40 wt% of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, preferably wherein at least a majority by weight of the antimicrobial agent (b) constitutes benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, such as at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, or all or substantially all of the antimicrobial agent (b) is benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

[0107] Embodiment 47 : The product formulation or method according to Embodiment 45 or 46, wherein the at least one additional antimicrobial or preservative material is chosen from salicylic acid, sorbic acid, lactic acid, acetic acid, formic acid, citric acid, hexa-2,4-dienoic acid, 4-hydroxybenzoic acid, salts thereof (such as salts of sodium, potassium, calcium, magnesium or ammonium, particularly salts of sodium or potassium, e.g., potassium sorbate or sodium sorbate), esters of 4-hydroxybenzoic acid (such as those of methyl, ethyl, propyl, isopropyl, butyl, isobutyl or phenyl, e.g., methylparaben, ethylparaben, propylparaben, butylparaben, etc.), dichlorobenzyl alcohol, phenethyl alcohol, hydroxyacetophenone, ethylhexylglycerin, chlorphene sin, pyrithiones (e.g., zinc pyrithione and / or sodium pyrithione), isothiazolinones (e.g., 5 -chloro-2 -methyl -4-isothiazolin-3 -one (CMIT), 2-methyl- 4-isothiazolin-3-one (MIT), l,2-benzisothiazolin-3-one (BIT), combinations thereof), ethyl lauroyl arginate (LAE) and combinations of the foregoing.

[0108] Embodiment 48: The product formulation or method according to any one of Embodiments 45-47, wherein the antimicrobial agent (b) consists essentially of, or consists of, benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof and the at least one additional antimicrobial or preservative material.

[0109] Embodiment 49: A method of synergistically enhancing the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, the method comprising combining or mixing the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof with a phenolic extract from algae, such as described in any one or more of Embodiments 2, 3, 9, and 10 above. Embodiment 50: The method according to Embodiment 49, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the phenolic extract is as described in Embodiment 11 above.

[0110] Embodiment 51 : The method according to Embodiment 49, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract is as described in Embodiment 12 above.

[0111] Embodiment 52: The method according to any one of Embodiments 49-51, wherein the antimicrobial efficacy is synergistically enhanced in an aqueous product formulation.

[0112] Embodiment 53: The method according to any one of Embodiments 49-52, wherein the antimicrobial efficacy is synergistically enhanced in a personal care, home care, health care, food or industrial product formulation.

[0113] Embodiment 54: The method according to any one of Embodiments 49-52, wherein the antimicrobial efficacy is synergistically enhanced in a personal care, home care, or health care product formulation.

[0114] Embodiment 55: The method according to any one of Embodiments 49-52, wherein the antimicrobial efficacy is synergistically enhanced in a food product formulation, and the method comprises combining or mixing benzoic acid and / or at least one salt thereof with the phenolic extract from algae.

[0115] Embodiment 56: The method according to Embodiment 55, wherein the method comprises combining or mixing at least one salt of benzoic acid with the phenolic extract from algae, preferably wherein the at least one salt of benzoic acid is sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof, more preferably sodium benzoate, potassium benzoate or a combination thereof, particularly sodium benzoate.

[0116] As used herein, the articles “a”, “an”, and “the” preceding an element or component of the invention are intended to be nonrestrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore “a”, “an”, and “the” should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.

[0117] As used herein, the term “comprising” means the presence of the stated features, integers, steps, or components as referred to in the claims, but that it does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. The term “comprising” is intended to include embodiments encompassed by the terms “consisting essentially of’ and “consisting of,” unless the context dictates otherwise.

[0118] As used herein, the term “about” modifying the quantity of an ingredient employed refers to variation in the numerical quantity that can occur, for example, through typical measuring and handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like.

[0119] Where present, all ranges are inclusive and combinable. For example, when a range of “1 to 5” is recited, the recited range should be construed as including ranges “1 to 4”, “1 to 3”, “1-2”, “1-2 & 4- 5”, “1-3 & 5”, and the like.

[0120] When a parameter is given either as a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range.

[0121] Further details in accordance with the present disclosure include, without limitation, the following Examples.

[0122] EXAMPLES

[0123] Example 1

[0124] Seaweed extraction

[0125] Dry brown algae (Ascophyllum nodosum) was ground and mixed with 65% acetone at a 1: 10 (w / v) of dry seaweed to acetone ratio. The mixture was incubated at 25 °C for 24 hours with shaking (200 RPM). After incubation, the mixture was centrifuged at 2000g for 15 minutes and the supernatant (extract) was collected. Acetone in the supernatant was removed using a Rotary evaporator. The remaining extract was further purified via DIAION HP20 resin Solid Phase Extraction. The column was eluted with 50% and 65% methanol. Eluents were then SpeedVac dried.

[0126] Phenolic content

[0127] Total phenolic content in the extract that was prepared according to the procedure above was determined according to the Folin-Ciocalteu method as described herein using phloroglucinol as the equivalent. The method was conducted using the following materials: 2N Folin Ciocalteu (FC) reagent; a sodium carbonate solution prepared by dissolving 50g of anhydrous sodium carbonate in 200 mb of water, bringing to a boil, cooling and thereafter adding a few crystals of sodium carbonate, letting sit for 24 hr, filtering and adding water to 250 mb; and standard phloroglucionol / water solutions at gradient concentrations. The procedure was carried out according to the microscale protocol (Waterhouse, A. L., “Determination of Total Phenolics,” Current Protocols in Food Analytical Chemistry, Vol. 6, 2002) as follows. 20 pL each of standard, sample, and control were pipetted into separate vials. To each vial, 1.58 mb of water and then 100 pL of the FC reagent were added and mixed well. After 30 second to 8 minutes, 300 pL of the sodium carbonate solution was added and mixed. The solutions were left at 40 °C for 30 minutes and the absorbance of each solution at 765 nm was determined. A standard curve of concentration against absorbance was created, and the standard curve was used to calculate the equivalent phloroglucinol concentrations in the samples. Results were reported as phloroglucinol equivalents. The extract that was prepared according to the seaweed extraction above had a phenolic content equivalent to 95 mg of phloroglucinol per 100 mg of dry extract.

[0128] Growth inhibition test

[0129] Fresh water solutions of sodium benzoate and the phenolic extract from Ascophyllum nodosum were prepared and mixed at different concentration ratios. The aliquots of these mixtures were then inoculated with Pseudomonas aeruginosa ATCC 15442 (final concentration of 107to 108CFU / mL) and Candida albicans ATCC 10231 (final concentration of 105to 106CFU / mL) respectively. Each mixture also contained 20% Mueller Hinton Broth and 1.6% glycerol. After incubating at 25 °C for 24 hours and at 30 °C for 3 days for bacteria and fungi inoculated aliquots, respectively, growth inhibition was assessed based on inspecting for visible growth. Antimicrobial efficacy was determined by the minimum tested concentration for inhibiting bacterial or fungal growth (MIC). Table 1 and 2 show the MIC of sodium benzoate, the phenolic extract from Ascophyllum nodosum and their combinations, as well as the Synergy Index of each combination, and the ratios of the components are provided based on the ratio of the weight of sodium benzoate to the weight of the phenolic extract and further based on the ratio of the weight of sodium benzoate to the total phenolic weight of the phenolic extract as represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

[0130] Synergy Index = Ca / CA + Cb / CB.

[0131] Ca: Concentration of A required to inhibit bacterial / fungal growth when used in combination.

[0132] CA: Concentration of A required to inhibit bacterial / fungal growth when used alone.

[0133] Cb: Concentration of B required to inhibit bacterial / fungal growth when used in combination.

[0134] CB: Concentration of B required to inhibit bacterial / fungal growth when used alone.

[0135] The Synergy Index value is interpreted as follows: < 1 is synergistic; equal to 1 is additive; and > 1 is antagonistic.

[0136] Table 1. MIC of sodium benzoate, the phenolic extract from algae, and their combinations against Pseudomonas aeruginosa ATCC 15442. benzoate to total

[0137] Synergy Synergy phenolic weight Index Index of the extract (phloroglucinol

[0138] Table 2. MIC of sodium benzoate, the phenolic extract from algae and their combinations against

[0139] Candida albicans ATCC 10231. Biocidal test

[0140] Fresh water solutions of sodium benzoate and the phenolic extract from Ascophyllum nodosum were prepared and mixed at different concentration ratios. The aliquots of these mixtures were then inoculated with Pseudomonas aeruginosa ATCC 15442 and Candida albicans ATCC 10231 at a final concentration of 107 to 108 CFU / mL and 105 to 106 CFU / mL, respectively. Each mixture also contained 30% PBS (pH7) and 1% Tryptic Soy Broth. After incubating at 30 °C for 24 hours, the viable bacteria in each mixture were determined using a serial dilution method. Biocidal efficacy was determined by the minimum tested concentration for 99.99% bacterial log reduction as compared to untreated control. Tables 3 and 4 show the biocidal efficacy of sodium benzoate, the phenolic extract from Ascophyllum nodosum and their combinations as well as the Synergy Index of each combination, and the ratios of the components are provided based on the ratio of the weight of sodium benzoate to the weight of the phenolic extract and further based on the ratio of the weight of sodium benzoate to the total phenolic weight of the phenolic extract as represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method. Synergy Index = Ca / CA + Cb / CB.

[0141] Ca: Concentration of A required to achieve a 99.99% bacterial / fungal reduction when used in combination.

[0142] CA: Concentration of A required to achieve a 99.99% bacterial / fungal reduction when used alone.

[0143] Cb: Concentration of B required to achieve a 99.99% bacterial / fungal reduction when used in combination.

[0144] CB: Concentration of B required to achieve a 99.99% bacterial / fungal reduction when used alone.

[0145] The Synergy Index value is interpreted as follows: < 1 is synergistic; equal to 1 is additive; and > 1 is antagonistic.

[0146] Table 3. Biocidal efficacy of sodium benzoate, the phenolic extract from algae and their combinations against Pseudomonas aeruginosa ATCC 15442.

[0147] Table 4. Biocidal efficacy of sodium benzoate, the phenolic extract from algae and their combinations against Candida albicans ATCC 10231.

[0148] The growth inhibition and biocidal studies demonstrate that the phenolic extract from algae synergistically enhances the antimicrobial activity of sodium benzoate (benzoic acid) against both bacteria and fungi at a wide range of mixing ratios, such as at least from 54: 1 (w / w) to 1:2208 (w / w) of sodium benzoate to the phenolic extract or at least from 57: 1 (w / w) to 1:2097 of sodium benzoate to the total phenolic weight of the phenolic extract as represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

[0149] Example 2

[0150] Seaweed extraction

[0151] Dry brown algae (Ascophyllum nodosum) was ground and mixed with water at a 1: 13 ratio (w / v) of dry seaweed to water and homogenized for 8 to 12 minutes using a BeadBeater (BIOSPEC Product). The same volume of ethanol as that of the water used in the homogenization was then added, and the mixture was incubated at 25 °C with shaking (200 RPM) for 24 hours. The mixture was then fdtered with Whatman Grade Q2 filter paper. The filtrate was collected and Rotavapor dried.

[0152] Phenolic content

[0153] Total phenolic content in the extract was determined according to the Folin-Ciocalteu method, as in Example 1 above. The extract had a phenolic content equivalent to 32 mg of phloroglucinol per 100 mg of dry extract.

[0154] Application challenge testing in personal care product formulation

[0155] A xanthan gum based skin care lotion formulation used in the testing contained (w / w) 79.7% water, 0.3% xanthan gum, 4% propylene glycol, 2% CreamMaker CA-20, 3% stearic acid, 2% glyceryl stearate, 2% petrolatum, 4% ethylhexyl olivate, and 3% isopropyl myristate. The pH was 5.2.

[0156] Aliquots of the formulation were dosed with the antimicrobial agent sodium benzoate, the phenolic extract from A. nodosum, and certain combinations of the antimicrobial agent and the phenolic

[0157] T1 extract. An untreated formulation was used as a negative control. The aliquots were then inoculated with a pool of fresh bacterial cultures at a final concentration around 106CFU / g and a pool of fresh fungal cultures at a final concentration around 105CFU / g. The bacterial pool included Enterobacter gergoviae 33028, Escherichia coli 8739, Klebsiella pneumoniae 13883, Pseudomonas aeruginosa 9027, Pseudomonas aeruginosa 15442, Pseudomonas putida 49128, Burkholderia cepacia 25416, Staphylococcus aureus 6538, and Staphylococcus epidermidis 12228. The fungal pool included Candida albicans 10231 and Aspergillus niger 16404. All aliquots were then incubated at 25 °C for 28 days. Re -inoculation was done for all aliquots after 7 days and viable bacteria or fungi in each aliquot were enumerated after 7 days (before re-inoculation), 14 days, 21 days and 28 days using the Streak- Plate method. Trypticase Soy Agar was used for bacterial enumeration and Potato Dextrose Agar was used for fungal enumeration. Growth rating was given based on the number of colonies present on each agar plate. The growth rating scale is shown in Table 5.

[0158] Table 5. Microbial growth and growth rating scale.

[0159] * CFU / g = colony forming units per gram of sample.

[0160] Tables 6 and 7 provide the bacterial growth ratings and fungal growth ratings, respectively, of the blank lotion formulation and the formulation dosed with the different materials as shown. In the samples dosed with the combinations of sodium benzoate and the phenolic extract, the weight ratios of the sodium benzoate to the phenolic extract were 1: 10 and 1: 15, respectively, and the ratios by weight of the sodium benzoate to the total phenolic weight of the phenolic extract were 1:3.2 and 1:4.8, respectively, (where the total phenolic weight was the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method).

[0161] Table 6.

[0162] Table 7.

[0163] Tables 6 and 7 show that at the same or lower concentrations, sodium benzoate combined with the phenolic extract from algae significantly outperformed each of sodium benzoate and the phenolic extract alone at many time points.

[0164] Example 3

[0165] A phenolic extract from Ascophyllum nodosum was prepared in a manner similar to Example 2 above. Total phenolic content in the extract was determined according to the Folin-Ciocalteu method, as in Example 1 above. The extract had a phenolic content equivalent to 26 mg of phloroglucinol per 100 mg of dry extract.

[0166] The same skin care lotion formulation from Example 2 was used to conduct testing using the same challenge test procedure for bacteria as described as above, except aliquots of the formulation were dosed with the antimicrobial agent potassium benzoate, benzyl alcohol or phenoxyethanol, the phenolic extract from A. nodosum, and certain combinations of the antimicrobial agent and the phenolic extract. The growth rating results are shown in Tables 8 to 10.

[0167] Table 8 provides the bacterial growth ratings of the blank lotion formulation and the formulation dosed with the different materials as shown. In the samples dosed with the combinations of potassium benzoate and the phenolic extract, the weight ratios of the potassium benzoate to the phenolic extract were 1: 10 and 1: 15, respectively, and the ratios by weight of the potassium benzoate to the total phenolic weight of the phenolic extract were 1:3.2 and 1:4.8, respectively, (where the total phenolic weight was the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method). Table 8.

[0168] Table 9 provides the bacterial growth ratings of the blank lotion formulation and the formulation dosed with the different materials as shown. In the samples dosed with the combinations of benzyl alcohol and the phenolic extract, the weight ratios of the benzyl alcohol to the phenolic extract were 1:6.7 and 1: 10, respectively, and the ratios by weight of the benzyl alcohol to the total phenolic weight of the phenolic extract were 1: 1.7 and 1:2.6, respectively, (where the total phenolic weight was the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method). Table 9.

[0169] Table 10 provides the bacterial growth ratings of the blank lotion formulation and the formulation dosed with the different materials as shown. In the samples dosed with the combinations of phenoxyethanol and the phenolic extract, the weight ratios of the phenoxyethanol to the phenolic extract were 1:6.7 and 1: 10, respectively, and the ratios by weight of the phenoxyethanol to the total phenolic weight of the phenolic extract were 1: 1.7 and 1:2.6, respectively, (where the total phenolic weight was the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method).

[0170] Table 10.

[0171] As shown in Tables 8 to 10, at the same or lower concentrations, the combinations significantly outperformed each of the antimicrobial agent and the phenolic extract alone at many time points.

Claims

What is claimed is:

1. An antimicrobial composition comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

2. The antimicrobial composition according to claim 1, wherein the antimicrobial agent comprises at least one salt of benzoic acid.

3. The antimicrobial composition according to claim 2, wherein the at least one salt of benzoic acid is sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combinations thereof.

4. The antimicrobial composition according to any preceding claim, wherein the phenolic extract has a phenolic content equivalent to at least 10 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

5. The antimicrobial composition according to claim 4, wherein the phenolic extract has a phenolic content equivalent to at least 50 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

6. The antimicrobial composition according to any preceding claim, wherein the phenolic extract is derived from brown algae.

7. The antimicrobial composition according to claim 6, wherein the brown algae is of the genus Ascophyllum.

8. The antimicrobial composition according to any preceding claim, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract ranges from about 50: 1 to about 1 : 100, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

9. The antimicrobial composition according to any preceding claim, wherein the composition is in a concentrated form comprising from 50 to 100 wt%, preferably from about 75 to 100 wt%, of the phenolic extract (a) and the antimicrobial agent (b) combined, based on the total weight of active ingredients in the antimicrobial composition.

10. The antimicrobial composition according to claim 9, further comprising from about 10 to about 95 wt%, based on the weight of the composition, of one or more solvents or carriers, preferably wherein the one or more solvents or carriers are chosen from water, water miscible materials and combinations thereof.

11. The antimicrobial composition according to claim 9, wherein the antimicrobial composition consists essentially of the phenolic extract (a), the antimicrobial agent (b), optionally one or more solvents or carriers (c), and optionally one or more excipients (d).

12. The antimicrobial composition according to any one of claims 1-8, wherein the antimicrobial composition is in the form of an aqueous product formulation, preferably a personal care, home care, health care, food or industrial product formulation.

13. The antimicrobial composition according to claim 12, wherein the antimicrobial effective amount of the combination of the phenolic extract (a) and the antimicrobial agent (b) ranges from about 0.05 wt% to about 10 wt%, based on the total weight of the product formulation.

14. A personal care, home care or health care product formulation comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof.

15. The personal care, home care or health care product formulation according to claim 14, wherein the antimicrobial agent comprises at least one salt of benzoic acid.

16. The personal care, home care or health care product formulation according to claim 15, wherein the at least one salt of benzoic acid is sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof.

17. The personal care, home care or health care product formulation according to any one of claims 14-16, wherein the phenolic extract has a phenolic content equivalent to at least 10 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin - Ciocalteu method.

18. The personal care, home care or health care product formulation according to claim 17, wherein the phenolic extract has a phenolic content equivalent to at least 50 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

19. The personal care, home care or health care product formulation according to any one of claims 14-18, wherein the phenolic extract is derived from brown algae.

20. The personal care, home care or health care product formulation according to claim 19, wherein the brown algae is of the genus Ascophyllum.

21. The personal care, home care or health care product formulation according to any one of claims 14-20, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract ranges from about 50: 1 to about 1: 100, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

22. The personal care, home care or health care product formulation according to any one of claims 14-21, wherein the antimicrobial effective amount of the combination ranges from about 0.05 wt% to about 10 wt%, based on the total weight of the product formulation.

23. A food product formulation comprising an antimicrobial effective amount of a combination of (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid and / or at least one salt thereof.

24. The food product formulation according to claim 23, wherein the antimicrobial agent comprises sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof.

25. The food product formulation according to claim 23 or 24, wherein the phenolic extract has a phenolic content equivalent to at least 10 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

26. The food product formulation according to claim 25, wherein the phenolic extract has a phenolic content equivalent to at least 50 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

27. The food product formulation according to any one of claims 23-26, wherein the phenolic extract is derived from brown algae.

28. The food product formulation according to claim 27, wherein the brown algae is of the genus Ascophyllum.

29. The food product formulation according to any one of claims 23-28, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof to the total phenolic weight of the phenolic extract ranges from about 50: 1 to about 1: 100, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

30. The food product formulation according to any one of claims 23-29, wherein the antimicrobial effective amount of the combination ranges from about 0.05 wt% to about 10 wt%, based on the total weight of the product formulation.

31. A method of killing or inhibiting the growth of microorganisms on a substrate or in a product formulation, comprising applying to the substrate or adding to the product formulation (a) a phenolic extract from algae, and (b) an antimicrobial agent comprising benzoic acid, and / or at least one salt thereof, benzyl alcohol, phenoxyethanol, or a combination thereof, and the phenolic extract (a) and the antimicrobial agent (b) are applied or added in an antimicrobial effective amount.

32. The method according to claim 31, wherein the antimicrobial agent comprises at least one salt of benzoic acid.

33. The method according to claim 32, wherein the at least one salt of benzoic acid is sodium benzoate, potassium benzoate, calcium benzoate, zinc benzoate or a combination thereof.

34. The method according to any one of claims 31-33, wherein the phenolic extract has a phenolic content equivalent to at least 10 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

35. The method according to claim 34, wherein the phenolic extract has a phenolic content equivalent to at least 50 mg phloroglucinol per 100 mg of extract on a dry weight basis determined according to the Folin-Ciocalteu method.

36. The method according to any one of claims 31-35, wherein the phenolic extract is derived from brown algae.

37. The method according to claim 36, wherein the brown algae is of the genus Ascophyllum.

38. The method according to any one of claims 31-37, wherein the ratio by weight of the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof to the total phenolic weight of the phenolic extract ranges from about 50: 1 to about 1: 100, where the total phenolic weight of the phenolic extract is represented by the total phloroglucinol equivalency weight in the extract determined according to the Folin-Ciocalteu method.

39. The method according to any one of claims 31-38, wherein the antimicrobial effective amount ranges from about 0.05 wt% to about 10 wt%, based on the total weight of the product formulation.

40. The method according to any one of claims 31-39, wherein the product formulation is a personal care, home care or health care product formulation.

41. The method according to any one of claims 31-39, wherein the product formulation is a food product formulation, and the antimicrobial agent comprises benzoic acid and / or at least one salt thereof.

42. A method of synergistically enhancing the antimicrobial efficacy of benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof, the method comprising combining or mixing the benzoic acid and / or at least one salt thereof, benzyl alcohol, phenoxyethanol or a combination thereof with a phenolic extract from algae.

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