Use of starch for achieving antimicrobial efficacy

Abstract

Disclosed is use of starch for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or the gene expression of human beta-defensin-4.

Description

[0001] USE OF STARCH FOR ACHIEVING ANTIMICROBIAL EFFICACY

[0002] Field of the Invention

[0003] The present invention relates to use of starch for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, and boosting innate defense to skin.

[0004] Background of the Invention

[0005] Skin is the primary line of defense that protects the human body from invading pathogens, like virus and bacteria. As a primary defense organ, the skin tissue always remains in constant contact with the environment and therefore it has to face and resolve threats and challenges from invading pathogens. The exposed skin surface is not only challenged by pathogenic foreign bacteria, but it also remains in contact and interacts with the resident commensal bacteria. In spite of all these challenges from such foreign microbes, healthy skin remains infection free and also the number of the resident microflora remains generally constant. This equilibrium in the interaction between the skin tissue and the microbes is maintained as the skin has sophisticated defense strategy of which anti-microbial peptides (AMPs) form an important part.

[0006] AMPs form an integral part of the skin’s own defense system. AMPs are ubiquitous in nature, and they typically exhibit a broad spectrum of activity against invading bacteria, fungi, viruses and parasites. AMPs are generally short peptides and in humans about 90 different AMPs are reported to be present. These antimicrobial peptides participate in the innate immune response by providing a rapid first-line defense against infection. AMPs play an essential role in maintaining an optimal and functional skin barrier, not only by direct killing of pathogens, but also by balancing immune responses.

[0007] The present inventors have recognized that there are needs to develop way of upregulating the gene expression for certain anti-microbial peptides, for example cathelicidin anti-microbial peptide (CAMP) or human beta-defensin-4 anti-microbial peptide (hBD4), then inducing secretion of anti-microbial peptide and thus it may provide benefits of protecting from microbial infection, boosting innate defense, and improving barrier function . It was surprisingly found that starch is capable of significantly upregulating the gene expression of anti-microbial peptide (CAMP) and human beta-defensin-4 anti-microbial peptide (hBD4). Summary of the Invention

[0008] In a first aspect, the present invention is directed to use of starch for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, and upregulating the gene expression of cathelicidin antimicrobial peptide or the gene expression of human beta- defensin-4 to skin.

[0009] In a second aspect, the present invention is directed to starch, or a cosmetic composition comprising starch for use in providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide, and upregulating the gene expression the gene expression of human beta-defensin-4.

[0010] In a third aspect, the present invention is directed to a method for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or human beta-defensin-4, comprising a step of topically applying to skin a composition comprising starch.

[0011] All other aspects of the present invention will more readily become apparent upon considering the detailed description and examples which follow.

[0012] Detailed Description of the Invention

[0013] Except in the examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and / or use may optionally be understood as modified by the word “about”.

[0014] All amounts are by weight of the composition, unless otherwise specified.

[0015] It should be noted that in specifying any range of values, any particular upper value can be associated with any particular lower value.

[0016] For the avoidance of doubt, the word “comprising” is intended to mean “including” but not necessarily “consisting of’ or “composed of”. In other words, the listed steps or options need not be exhaustive. The disclosure of the invention as found herein is to be considered to cover all embodiments as found in the claims as being multiply dependent upon each other irrespective of the fact that claims may be found without multiple dependency or redundancy.

[0017] Where a feature is disclosed with respect to a particular aspect of the invention (for example a composition of the invention), such disclosure is also to be considered to apply to any other aspect of the invention (for example a method of the invention) mutatis mutandis.

[0018] Preferably, the benefit is selected from the group consisting of inducing secretion of antimicrobial peptide in skin, protecting skin from microbial infection, improving skin barrier function, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4. More preferably, the benefit is selected from the group consisting of inducing secretion of anti-microbial peptide in skin, protecting skin from microbial infection, and improving skin barrier function. Even more preferably, the benefit is selected from the group consisting of protecting skin from microbial infection and inducing secretion of anti-microbial peptide in skin.

[0019] Preferably, the benefit is selected from the group consisting of protecting skin from microbial infection, improving skin barrier function, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4. More preferably, the benefit is selected from the group consisting of inducing secretion of antimicrobial peptide in skin, protecting skin from microbial infection, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4. More preferably, the benefit is selected from the group consisting of upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4.

[0020] Typically, the starch is provided with effective amount. Effective amount as used herein, refers to the amount of starch sufficient to induce a positive benefit, where the positive benefit refers to an increase equal to or greater than 1%, preferably at least 2%, more preferably at least 5%, even more preferably at least 10%, still even more preferably at least 20%, still even more preferably at least 35%, and particularly preferably at least 60% of gene expression of at least one of CAMP and hBD4 genes, relative to blank control. Typically, the starch is not use as prebiotic according to the present invention. The term “prebiotic” as used herein is ingredient fostering beneficial bacteria.

[0021] Starch as used herein refers to component selected from the group consisting of native starch, modified starch and combinations thereof. The term “native starch” as used herein refers to a starch that has been isolated from a natural plant source and that has not been hydrolyzed or chemically modified. The term “modified starch” as used herein refers to a starch that has been chemically modified, preferably by esterification.

[0022] Preferably the starch comprises native starch and more preferably is native starch. Preferably, the native starch is selected from potato starch, tapioca starch, maize starch, and sweet potato starch. More preferably the native starch is maize starch.

[0023] Preferably the modified starch comprises hydroxyalkylated starch, carboxyalkylated starch, succinated starch, or a mixture thereof. More preferably the modified starch comprises hydroxypropylated starch, hydroxyethylated starch, carboxymethylated starch, octenylsuccinated starches, dodecylsuccinated starch or a mixture thereof.

[0024] Preferably, the starch of the present invention has a molar ratio of amylose to amylopectin of from 1:99 to 99:1, more preferably 20:80 to 80:20, even more preferably 20:80 to 30:70.

[0025] Preferably, the native starch of the present invention has a molar ratio of amylose to amylopectin is from 1:99 to 99:1, more preferably 20:80 to 80:20, even more preferably 20:80 to 30:70.

[0026] Preferably, the starch has a bulk density of 200 to 1000 g / L, more preferably 300 to 800 g / L and even more preferably 400 to 600 g / L. Preferably, the native starch has a bulk density of 200 to 1000 g / L, more preferably 300 to 800 g / L and even more preferably 400 to 600 g / L.

[0027] Preferably, the starch is present in amount of 0.0001 to 45% by weight of the composition. More preferably, the starch is present in amount of 0.001 to 30% by weight of the composition and even more preferably 0.005 to 8% by weight of composition. Preferably, the native starch is present in amount of 0.0001 to 45% by weight of the composition. More preferably, the native starch is present in amount of 0.001 to 30% by weight of the composition and even more preferably 0.005 to 8% by weight of composition. Alternatively, the starch may be present in amount of 0.0001 to 12%, more preferably 0.001 to 8%, and even more preferably 0.005 to 8% by weight of the composition. The native starch may be present in amount of 0.0001 to 12%, more preferably 0.001 to 8%, and even more preferably 0.005 to 8% by weight of the composition.

[0028] Preferably, the starch has a weight average molecular weight of at least 1 KDa, more preferably at least 10 KDa and even more preferably at least 100 KDa. Preferably, the starch has a weight average molecular weight of no greater than 100,000,000 KDa, more preferably no greater than 10,000,000 KDa and even more preferably no greater than 1 ,000,000 KDa. Preferably, the native starch has a weight average molecular weight of at least 1 ,000, more preferably at least 1 KDa, more preferably at least 10 KDa and even more preferably at least 100 KDa. Preferably, the starch has a weight average molecular weight of no greater than 100,000,000 KDa, more preferably no greater than 10,000,000 KDa and even more preferably no greater than 1 ,000,000 KDa.

[0029] The starch is preferably in a cosmetic composition. The composition of the present invention may be skin cleansing composition, skin care composition, hair care composition, oral care composition, or deodorant compositions. The composition may be in the form of a solid, soft solid, liquid, emulsion, microemulsion, lotion, cream, gel, or aerosol forms.

[0030] The composition preferably comprises a cleansing surfactant. More than one cleansing surfactant may be included in the composition. The cleaning surfactant may be chosen from soap, non-soap anionic, cationic, non-ionic, amphoteric surfactant and mixtures thereof. Many suitable surface-active compounds are available and are fully described in the literature, for example, in "Surface-Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch. The preferred surface-active compounds that can be used are soaps, non-soap anionic, non-ionic surfactant, amphoteric surfactant or a mixture thereof.

[0031] Suitable non-soap anionic surfactants include linear alkylbenzene sulphonate, primary and secondary alkyl sulphates, particularly Cs to C15 primary alkyl sulphates; alkyl ether sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates; fatty acid ester sulphonates; or a mixture thereof. Sodium salts are generally preferred.

[0032] Most preferred non-soap anionic surfactant are linear alkylbenzene sulphonate, particularly linear alkylbenzene sulphonates having an alkyl chain length of from Cs to C15. It is preferred if the level of linear alkylbenzene sulphonate is from 0 wt% to 30 wt%, more preferably from 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%, by weight of the total composition.

[0033] Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the Cs to C20 aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C10 to C15 primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol. Non ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide). It is preferred if the level of non-ionic surfactant is from 0 wt% to 30 wt%, preferably from 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%, by weight of a fully formulated composition comprising the microcapsules of the invention.

[0034] Suitable amphoteric surfactants preferably are betaine surfactants. Examples of suitable amphoteric surfactants include, but are not limited to, alkyl betaines, alkylamido betaines, alkyl sulfobetaines, alkyl sultaines and alkylamido sultaines; preferably, those having 8 to 18 carbons in the alkyl and acyl group. It is preferred that the amount of the amphoteric surfactant is 0 to 20 wt%, more preferably from 1 to 10 wt%, by weight of the composition.

[0035] It is also possible to include certain mono-alkyl cationic surfactants. Cationic surfactants that may be used include quaternary ammonium salts of the general formula R1R2R3R4N+X' wherein the R groups are long or short hydrocarbon chains, typically alkyl, hydroxyalkyl or ethoxylated alkyl groups, and X is a counter-ion (for example, compounds in which R1is a C8-C22 alkyl group, preferably a Cs-C or C12-C14 alkyl group, R2is a methyl group, and R3and R4, which may be the same or different, are methyl or hydroxyethyl groups); and cationic esters (for example, choline esters).

[0036] The composition may comprise soap. The soap is preferably a C8-C24 soap, more preferably C10-C20 soap and most preferably C12-C18 soap. The cation of the soap can be alkali metal, alkaline earth metal or ammonium. Preferably, the cation of the soap is selected from sodium, potassium or ammonium. More preferably the cation of the soap is sodium or potassium. Fatty acids derived from other suitable oils / fats such as groundnut, soybean, tallow, palm, palm kernel, etc. may also be used in other desired proportions. Soap is preferably present in an amount of 1 to 90%, preferably from 10 to 85%, more preferably 25 to 75% by weight of the composition. The composition is preferably in the form of a solid or semi solid form, more preferably in a solid form. Even more preferably the composition is a soap bar. Preferably, the composition is a skin cleansing composition. When water is present, it is preferably present in at least 1%, more preferably at least 2%, even more preferably at least 5% by weight of the composition. When water is the carrier, a preferred composition comprises 10 to 50%, more preferably 12 to 40% by weight water. Starch or native starch may be present from 5 to 45%, more preferably from 8 to 40% and most preferably from 10 to 35% by weight of the composition.

[0037] Water-soluble skin benefit agents may optionally be formulated into the compositions of the invention. A variety of water-soluble skin benefit agents can be used, and the level can be from 0.1 to 50% but preferably from 1 to 30% by weight of the composition. These materials include, but are not limited to, polyhydroxy alcohols. Preferred water-soluble skin benefit agents are glycerin, sorbitol and polyethylene glycol.

[0038] Water-insoluble skin benefit agents may also be formulated into the compositions as conditioners and moisturizers. Examples include silicone oils; hydrocarbons such as liquid paraffins, petrolatum, microcrystalline wax, and mineral oil; and vegetable triglycerides such as sunflower seed and cottonseed oils.

[0039] Some compositions may include thickeners. These may be selected from cellulosics, natural gums and acrylic polymers but not limited by this thickening agent types. Among the cellulosics are sodium carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl methylcellulose and combinations thereof. Suitable gums include xanthan, pectin, karaya, agar, alginate gums and combinations thereof. Among the acrylic thickeners are homopolymers and copolymers of acrylic and methacrylic acids including carbomers such as Carbopol 1382, Carbopol 982, llltrez, Aqua SF-1 and Aqua SF-2 available from the Lubrizol Corporation. Amounts of thickener may range from 0.01 to 3% by weight of the active polymer (outside of solvent or water) in the compositions.

[0040] Preservatives can desirably be incorporated into the compositions of this invention to protect against the growth of potentially harmful microorganisms. Particularly preferred preservatives are phenoxyethanol, methyl paraben, propyl paraben, imidazolidinyl urea, sodium dehydroacetate and benzyl alcohol. The preservatives should be selected having regard for the use of the composition and possible incompatibilities between the preservatives and other ingredients. Preservatives are preferably employed in amounts ranging from 0.01% to 2% by weight of the composition.

[0041] Preferably the composition comprises water in an amount of at least 5% by weight of the composition, more preferably at least 25%, even more preferably 40 to 90% and still even more preferably at least 60 to 85% by weight of the composition.

[0042] Preferably, the composition has a viscosity of at least 5 mPa s, more preferably in the range 8 to 10000 mPa s, even more preferably 10 to 1000 mPa s, and most preferably 20 to 200 mPa s, when measured at 20 degrees C at a relatively high shear rate of 20 s’1. Preferably, the composition is in the form of fluid.

[0043] The cosmetic composition refers to a composition suitable for topical application to human skin, preferably is a rinse-off product. The term "rinse-off" as used with reference to compositions herein means a composition that is applied to or rubbed on the skin, and then washed off. Typically, the use is on desired skin surface. The term "skin" as used herein may include the skin on the face, scalp, neck, chest, abdomen, back, arms, under arms, hands, oral cavity, body and / or legs.

[0044] For sake of clarity, the composition comprises starch typically provides a greater benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4 in comparison to same composition comprises no starch.

[0045] The present invention also provides starch or composition comprises native starch for use in a method for providing benefit selecting from the group consisting of inducing secretion of antimicrobial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4.

[0046] The present invention also provides use of starch for the manufacture of a medicament for provide benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or and upregulating the gene expression of human beta-defensin-4.

[0047] The present invention also provides native starch or composition comprises native starch for use in a method for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4 to skin.

[0048] For sake of clarity, the composition comprises native starch typically provides a greater benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or human beta-defensin-4, in comparison to same composition comprises no native starch.

[0049] The present invention also provides native starch or composition comprises native starch for use in a method for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4.

[0050] The present invention also provides use of native starch for the manufacture of a medicament for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide and upregulating the gene expression of human beta-defensin-4.

[0051] The present invention also provides a method for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or the gene expression of human beta-defensin-4, comprising a step of topically applying to skin a composition comprising native starch.

[0052] Preferably the use is non-therapeutic. Preferably the method is non-therapeutic. The term non- therapeutic typically means for cosmetic purposes and not curative or therapeutic purposes. Examples

[0053] Example 1

[0054] This example demonstrates that upregulation of gene expression of cathelicidin anti-microbial peptide (CAMP) or gene expression of Human beta-defensin-4 (hBD4) by starch.

[0055] Reconstructed human equivalent skin model was provided by Biocell Biotech (Epikuitis®, Lot: ES240703, China). Epikuitis® models of non-treatment (NT) group were incubated for six days with daily culture medium refreshment. For SQOOH (squalene hydroperoxide) treatment group, Epikuitis® models were cultured for four days with daily culture medium refreshment till treatment. On Day 5, Epikuitis® models were treated with 10pL of 1 wt% of SQOOH topically and incubated for another 24 hours before sample collection. In the starch group, 5pL of 0.1 wt% of starch mixture was applied on the top of Epikuitis® models followed by SQOOH application on Day 5. After treatment, the Epikuitis® models were also incubated for another 24 hours till harvest.

[0056] Upon collection, samples were homogenized in AG RNAex Pro Reagent (Accurate Biotechnology, AG21102, China) with T 10 basic ULTRA-TURRAX® (IKA, Germany) and total RNA was extracted with chloroform. The extracted RNA was quantified using Nanodrop spectrometer (Thermo Fisher Scientific, Waltham, US) and reverse transcribed to generate the template cDNA using the Evo M-MLV (Accurate Biotechnology, AG11728, China) according to manufacturer’s protocol. Amplification of CAMP or hBD4 was performed with SYBR Green Premix Pro Taq HS qPCR Kit (Accurate Biotechnology, AG11701 , China) on CFX96 Touch Real-Time PCR Detection System (BioRad, US). The beta-actin gene was selected as the housekeeping gene. The relative expression of the target genes was normalized to housekeeping gene. The fold changes of active treated samples relative to the control were calculated (2(-AACt)) and used for comparison between treatments.

[0057] Table 1 a: Maize starch standard, procured from ROQUETTE. The maize for making this starch was sourced from China.

[0058] #: significantly better (p<0.01) than SQOOH The data in Table 1 indicates the CAMP and hBD4 gene expression were unexpectedly significantly upregulated by starch.

Claims

Claims1. Use of starch for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or the gene expression of human beta-defensin-4.

2. The use according to claim 1 wherein the use is non-therapeutic.

3. The use according to claim 1 or 2 wherein the starch is native starch.

4. The use according to any one of the preceding claims wherein the benefit is selected from the group consisting of protecting from microbial infection and improving immunity.

5. The use according to any one of the preceding claims wherein the starch has a molar ratio of amylose to amylopectin is from 20:80 to 80:20.

6. The use according to any one of the preceding claims wherein the starch has a bulk density of 200 to 1000 g / L.

7. The use according to any one of the preceding claims wherein the starch has a weight average molecular weight of at least 1 KDa and no greater than 100,000,000 KDa, preferably at least 100 KDa and no greater than 1,000,000 KDa.

8. The use according to any one of the preceding claims wherein the starch is present in a cosmetic composition.

9. The use according to claim 7 wherein the starch is present in amount of 0.0001 to 45% by weight of the composition, preferably 0.001 to 30% by weight of the composition.

10. The use according to claim 7 or 8 wherein the composition comprises starch provides a greater benefit in comparison to same composition comprises no starch.

11. Starch, or a cosmetic composition comprising starch for use in providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating thegene expression of cathelicidin antimicrobial peptide or the gene expression of human beta-defensin-4.

12. A method for providing benefit selecting from the group consisting of inducing secretion of anti-microbial peptide, protecting from microbial infection, improving barrier function, boosting innate defense, upregulating the gene expression of cathelicidin antimicrobial peptide or the gene expression of human beta-defensin-4, comprising a step of topically applying to skin a composition comprising starch.

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