Agents and methods for suppressing the number of Malassezia fungi, and agents and methods for preventing or improving a specified disease or ill health condition.

Abstract

To provide techniques for reducing malassezia counts.SOLUTION: An agent for reducing malassezia counts contains at least one selected from the following components (a)-(d) as an active ingredient: (a) erythritol, (b) xylitol, (c) reduced syrup with a sugar composition where monosaccharides account for less than 30 mass% and pentoses or greater make up less than 50 mass%, and (d) reduced syrup derived from the reduction of syrup with a dextrose equivalent of 30 or more and 50 or less. The present invention can Inhibit the proliferation of Malassezia fungi with no concerns about skin irritation or safety.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an agent for inhibiting the bacterial count of fungi of the genus Malassezia, and an agent for preventing or ameliorating a specific disease or unhealthy condition, which contain erythritol, xylitol or medium-saccharified reduced starch syrup as an active ingredient. [Background technology]

[0002] The genus Malassezia is a yeast-like fungus that is normally present on the skin of humans and animals, and 22 species are currently known (Non-Patent Document 1). This fungus requires lipids to grow, but since it cannot synthesize fatty acids by itself, it is found in large amounts in areas of the body where there is a lot of sebum. This fungus is also found in healthy skin, but it has been reported that when it grows excessively or in skin with a weakened barrier function, it can cause various diseases or unhealthy conditions, or be an aggravating factor for these conditions. Known diseases and unhealthy conditions in which this fungus is involved in the onset or exacerbation include, for example, tinea versicolor (Non-Patent Documents 1, 2, 3, 5, 6), Malassezia folliculitis (Non-Patent Documents 3, 5, 6, 7), seborrheic dermatitis (Non-Patent Documents 1, 3, 5, 6, 7), dandruff (Non-Patent Documents 1, 6), atopic dermatitis (Non-Patent Documents 3, 4, 5), as well as skin itching, which is a symptom of these diseases (Non-Patent Document 4, etc.), Malassezia otitis externa (Non-Patent Document 7), and Malassezia septicemia (Non-Patent Document 5). [Prior art documents] [Non-patent literature]

[0003] [Non-Patent Document 1] WIKIPEDIA The Free Encyclopedia, Malassezia, [Retrieved January 31, 2023], Internet<URL: https: / / en.wikipedia.org / wiki / Malassezia> [Non-Patent Document 2] Merck & Co., Inc., Kenilworth, NJ, USA, MSD Manual Home Edition, 17. Skin Disorders, Fungal Skin Infections, Tinea Versicolor, Author: Danise M. Aaron, Medically Reviewed, February 2020, [Retrieved January 31, 2023], Internet <URL: https: / / www.msdmanuals.com / ja-jp / %E3%83%9B%E3%83%BC%E3%83%A0 / 17-%E7%9A%AE%E8%86%9A%E3%81%AE%E7%97%85%E6%B0%97 / %E7%9A%AE%E8%86%9A%E7%9C%9F%E8%8F%8C%E6%84%9F%E6%9F%93%E7%97%87 / %E7%99%9C%E9%A2%A8?query=%E7%99%9C%E9%A2%A8> [Non-Patent Document 3] Ryoji Tsuboi, Malassezia, Allergy Glossary Series, Allergy 65(10), pp. 1282-1283, 2016 [Non-Patent Document 4] Hiroshima University, Public Relations and Press, Press Release, FY2013, Identification of the causative substance of sweat allergy in patients with atopic dermatitis, June 6, 2013, [Retrieved January 31, 2023], Internet<URL:https: / / www.hiroshima-u.ac.jp / koho_press / press / 2013 / 2013_024> [Non-Patent Document 5] Yoshihiro Kiyo, Malassezia-related diseases, Jpn. J. Med. Mycol., Vol.47, pp. 75-80, 2006 [Non-Patent Document 6] Gupta et al, CLINICAL REVIEW Skin diseases associated with Malassezia species, J AM ACAD DERMATOL, VOLUME 51, NUMBER 5, NOVEMBER 2004, pp. 785-798 [Non-Patent Document 7] H. Ruth Ashbee and E. Glyn V. Evans, Immunology of Diseases Associated with Malassezia Species, CLINICAL MICROBIOLOGY REVIEWS, Vol. 15, No. 1, Jan. 2002, p. 21?57 Summary of the Invention [Problem to be solved by the invention]

[0004] Therefore, it is believed that by suppressing the number of fungi of the genus Malassezia in the body, it is possible to suppress the occurrence or deterioration of diseases and unhealthy conditions caused or aggravated by these fungi, and to keep the body, including the skin, healthy. Therefore, an object of the present invention is to provide a technology for suppressing the number of fungi of the genus Malassezia. [Means for solving the problem]

[0005] As a result of intensive research, the present inventors have found that erythritol, xylitol and medium sugar content reduced starch syrup can inhibit the growth of fungi of the genus Malassezia. Based on this finding, the present inventors have completed the following inventions.

[0006] (1) The agent for suppressing the number of fungi of the genus Malassezia according to the present invention contains, as an active ingredient, any one or more selected from the following (A) to (D): (A) Erythritol, (a) Xylitol, (C) Reduced starch syrup having a sugar composition of less than 30% by mass of monosaccharides and less than 50% by mass of 5 or more sugars (medium sugar content reduced starch syrup); (e) Reduced starch syrup (medium sugar content reduced starch syrup) obtained by reducing starch syrup having a dextrose equivalent of 30 to 50.

[0007] (2) The agent for preventing or ameliorating one or more diseases selected from tinea versicolor, seborrheic dermatitis, dandruff, Malassezia folliculitis, atopic dermatitis, and Malassezia otitis externa according to the present invention comprises, as an active ingredient, any one or more selected from the following (A) to (D): (A) Erythritol, (a) Xylitol, (C) Reduced starch syrup having a sugar composition of less than 30% by mass of monosaccharides and less than 50% by mass of 5 or more sugars (medium sugar content reduced starch syrup); (e) Reduced starch syrup (medium sugar content reduced starch syrup) obtained by reducing starch syrup having a dextrose equivalent of 30 to 50.

[0008] (3) The agent according to the present invention may be used as an external preparation. Effect of the Invention

[0009] According to the present invention, the proliferation of fungi of the genus Malassezia can be inhibited, and therefore, according to the present invention, the proliferation of fungi of the genus Malassezia can be inhibited, and thus, the present invention can contribute to the prevention or improvement of diseases and unhealthy conditions in which fungi of the genus Malassezia are involved in the onset or aggravation, such as tinea versicolor, Malassezia folliculitis, seborrheic dermatitis, dandruff, atopic dermatitis, itchy skin, Malassezia otitis externa, Malassezia sepsis, and seborrheic keratosis.

[0010] In addition, erythritol, xylitol and medium sugar content reduced starch syrup, which are the active ingredients of the present invention, are also used as foods or food additives, which is evident from their extremely safe properties for humans and animals. Therefore, according to the present invention, the proliferation of fungi of the genus Malassezia can be inhibited without any concerns about irritation or safety to the skin or other living organisms. [Brief description of the drawings]

[0011] [Figure 1] 1 is a bar graph showing the turbidity of the culture medium obtained by culturing M. furfur in a medium containing 10 (w / v)% of the test substances (erythritol, xylitol, mannitol and sorbitol). [Diagram 2] 1 is a bar graph showing the turbidity of the culture medium obtained by culturing M. restricta in a medium containing 5 (w / v)% of the test substances (erythritol, xylitol, mannitol and sorbitol). [Diagram 3]This is a bar graph showing the turbidity of the culture medium obtained by culturing M. furfur in a medium containing 2.5 (w / v)% of the test substances (glycerol, medium sugar content reduced starch syrup, medium sugar content reduced starch syrup, and low sugar content reduced starch syrup). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] The present invention will be described in detail below. The present invention provides an agent for suppressing the bacterial count of fungi of the genus Malassezia and an agent for preventing or improving a specific disease or unhealthy condition. In this specification, these agents may be collectively referred to as "the agent of the present invention" or "the agent" to refer to any one of the agents.

[0013] "Malassezia" refers to microorganisms belonging to the genus Malassezia. Specific examples of the genus Malassezia include Malassezia arunalokei (e.g., strain NCCPF127130), Malassezia brasiliensis, Malassezia caprae (e.g., strain JCM14561), Malassezia cuniculi (e.g., strain CBS11721), Malassezia dermatis (e.g., strain JCM11348), Malassezia equi, Malassezia equina (e.g., strain JCM14562), Malassezia furfur (e.g., strain JCM9199, strain NBRC0656?), Malassezia globosa (e.g., strain NBRC101597), Malassezia japonica (e.g., strain NBRC 101603, strain JCM11963), Malassezia muris, Malassezia nana (e.g., strain JCM12085), Malassezia obtusa (e.g., strain CBS7876), Malassezia Examples of such bacteria include Malassezia ochoterenai, Malassezia pachydermatis (e.g., NBRC0995 strain, JCM10131 strain), Malassezia psittaci, Malassezia restricta (e.g., NBRC103918 strain), Malassezia slooffiae (e.g., CBS7956 strain), Malassezia sympodialis (e.g., JCM8503 strain, NBRC 113671 strain), Malassezia tropica, Malassezia vespertilionis (e.g., CBS15041 strain), and Malassezia yamatoensis (e.g., JCM12262 strain).

[0014] In the present invention, the term "bacterial count" refers to the number of microorganisms.

[0015] Whether the number of bacteria of the genus Malassezia is suppressed or not can be judged by a culture test as shown in the examples described later. That is, the same type of medium is prepared, one with the addition of this agent and the other without it. After inoculating the present bacteria into both media and culturing for a predetermined period of time, the amount of bacteria in the medium is measured. The amount of bacteria can be measured simply by the turbidity method, but a known method such as the dry cell weight method, the wet weight method, or the real-time PCR method can be appropriately selected depending on the medium, culture conditions, and the type of bacteria to be measured. As a result, if the amount of bacteria is smaller in the medium with the addition of this agent than in the medium without the addition of this agent, it can be judged that the number of bacteria of the genus Malassezia is suppressed by this agent.

[0016] Erythritol is a sugar alcohol that is naturally found in fruits such as grapes and pears, and in fermented foods such as miso, soy sauce, and sake. Its chemical name is 1,2,3,4-butaneterol, and it is a four-carbon monosaccharide alcohol. It is a reduced form of erythrose, but is obtained industrially by fermentation.

[0017] Xylitol is a pentose monosaccharide alcohol that is naturally found in many fruits and vegetables, such as plums, strawberries, and cauliflower, and is a reduced form of xylose.

[0018] Reduced starch syrup is a type of sugar alcohol obtained by reducing starch syrup. The raw material starch syrup is obtained by hydrolyzing (saccharifying) starch with acids or enzymes, and is a mixture of monosaccharides (glucose) and polysaccharides (oligosaccharides, dextrin, etc.). Therefore, reduced starch syrup is also a mixture containing two or more types of sugar alcohols, including monosaccharide sugar alcohols and polysaccharide (disaccharides, trisaccharides, tetrasaccharides, or pentasaccharides or more) sugar alcohols.

[0019] Reduced starch syrup may generally be divided into high saccharification reduced starch syrup, medium saccharification reduced starch syrup, and low saccharification reduced starch syrup depending on the degree of saccharification. The present inventors have found that among reduced starch syrups, "medium saccharification reduced starch syrup" with a medium degree of saccharification is particularly capable of suppressing the number of bacteria of the genus Malassezia. Examples of the sugar composition of medium saccharification reduced starch syrup include (a) less than 30% by mass of monosaccharides and less than 50% by mass of pentasaccharides or more, and more specifically, (d) 2-10% by mass of monosaccharides, 15-55% by mass of disaccharides, 15-65% by mass of trisaccharides, 1-15% by mass of tetrasaccharides, and 1-38% by mass of pentasaccharides or more.

[0020] The "sugar composition" refers to the mass percentage of each sugar relative to the total mass of sugars. In other words, it is the mass percentage of each sugar when the total mass of sugars is taken as 100.

[0021] The sugar composition can be confirmed using high performance liquid chromatography (HPLC). That is, reduced starch syrup or starch syrup is subjected to HPLC as a sample to obtain a chromatogram. In the chromatogram, the sum of the areas of all peaks corresponds to the "total mass of sugars," and the area of ​​each peak corresponds to the "mass of each sugar." Therefore, the mass percentage of each sugar in the sample can be calculated as the ratio of the area of ​​each peak to the sum of the areas of all peaks detected. The HPLC conditions can be set appropriately according to a standard method, and the following conditions can be exemplified. HPLC conditions Column: MCI GEL CK04S (10mm ID x 200mm) Eluent; high purity water Flow rate; 0.4mL / min Injection volume: 20μL Column temperature: 65°C Detection: Differential refractive index detector RI-10A (Shimadzu Corporation)

[0022] Reduced starch syrup can also be specified by the dextrose equivalent of the starch syrup used as the raw material. "Dextrose equivalent (DE)" is a value used as an index of the degree of decomposition of starch syrup, and is the ratio (percentage) of reducing sugars in a sample to the total solid content when the reducing sugars are measured as glucose. The maximum DE value is 100, which means that all of the solid content is glucose, and the smaller the DE, the more oligosaccharides and polysaccharides there are.

[0023] In the present invention, the DE of the raw material starch syrup for medium sugar content reduced starch syrup can be, for example, 30 or more, 31 or more, 32 or more, 40 or less, 42 or less, 44 or less, 46 or less, 48 ​​or less, or 50 or less.

[0024] The DE of starch syrup can be measured by the following method. <<DE measurement method>> Accurately weigh out 2.5 g of sample and dissolve in water to make 200 mL. Measure out 10 mL of this solution, add 10 mL of 1 / 25 mol / L iodine solution (note 1) and 15 mL of 1 / 25 mol / L sodium hydroxide solution (note 2), and leave in the dark for 20 minutes. Next, add 5 mL of 2 mol / L hydrochloric acid (note 3), mix, and then titrate with 1 / 25 mol / L sodium thiosulfate solution (note 4). When the solution turns slightly yellow near the end of the titration, add 2 drops of starch indicator (note 5) and continue the titration. The end point is when the color of the solution disappears. Measure the blank value using water and calculate the DE using the following formula 1. TIFF2024122292000002.tif49165

[0025] (Note 1) 1 / 25 mol / L iodine solution: Place 20.4 g of potassium iodide and 10.2 g of iodine in a 2 L measuring flask, dissolve in a small amount of water, and then add water up to the marked line. (Note 2) 1 / 25 mol / L sodium hydroxide solution: Place 3.2 g of sodium hydroxide in a 2 L measuring flask, dissolve it in a small amount of water, and then add water up to the marked line. (Note 3) 2 mol / L hydrochloric acid: Gradually add 150 mL of hydrochloric acid to 750 mL of water while stirring. (Note 4) 1 / 25 mol / L sodium thiosulfate solution: Place 20 g of sodium thiosulfate in a 2 L measuring flask, dissolve it in a small amount of water, and then add water up to the marked line. (Note 5) Starch indicator: Dissolve 5 g of soluble starch in 500 mL of water, and dissolve 100 g of sodium chloride in this.

[0026] Erythritol, xylitol and medium sugar content reduced starch syrup may be used as they are commercially available or may be produced according to a method known to those skilled in the art. These sugar alcohols may be used in any form, such as liquid, powder, or granule. Examples of commercially available products related to medium sugar content reduced starch syrup include "Aquaol #1" and "SE 57" (both from Bussan Food Science).

[0027] A known method for producing medium-saccharified reduced starch syrup is a reduction reaction in which hydrogen is added to the medium-saccharified starch syrup as the raw material. The reduction reaction by hydrogen addition may be carried out, for example, by charging a 40-75% by mass raw material sugar aqueous solution together with a reduction catalyst into a high-pressure reactor, setting the hydrogen pressure in the reactor to 4.9-19.6 MPa and the reaction liquid temperature to 70-180°C, while mixing and stirring, until hydrogen absorption is no longer observed. Thereafter, the reduction catalyst is separated, and the mixture is decolorized and desalted by ion exchange resin treatment, and if necessary, activated carbon treatment, etc., and then concentrated to a predetermined concentration to produce a high-concentration medium-saccharified reduced starch syrup.

[0028] The agent suppresses the number of bacteria of the genus Malassezia, which, as described above, inhabits the body surface of humans and animals in living organisms. Therefore, in one embodiment, the agent can be used as a preparation that acts on the body surface, i.e., as an external preparation.

[0029] Examples of the topical agent of the present invention include those that are directly applied, attached, sprayed, etc. to the skin (cosmetics, quasi-drugs, pharmaceuticals), as well as hygiene products such as skin cleansers, hair cleansers, and bath additives. Examples of the product dosage form include liquids, aerosols, roll-ons, sticks, creams, sheets, lotions, emulsions, gels, powders, tablets, etc. Products containing the agent can be produced by adding erythritol, xylitol, and / or medium-sugar reduced starch syrup to raw materials normally used in the product (for example, components such as solvents, dispersion media, excipients, oils, surfactants, alcohols, preservatives, chelating agents, antioxidants, thickeners, pH adjusters, fragrances, and bactericides).

[0030] The amount (content) of erythritol, xylitol and / or medium sugar reduced starch syrup used can be appropriately set according to the purpose of the product, the desired feeling of use, the product's dosage form or type, and the type and amount of other raw ingredients. The total mass of the product containing the sugar alcohol is 100% by mass, and the lower limit of the solid content concentration of the sugar alcohol can be 0.01% by mass or more, 0.02% by mass or more, 0.03% by mass or more, 0.04% by mass or more, or 0.05% by mass or more. The upper limit can be 35% by mass or less, 34% by mass or less, 33% by mass or less, 32% by mass or less, 31% by mass or less, 30% by mass or less, 29% by mass or less, 28% by mass or less, 27% by mass or less, 26% by mass or less, 25% by mass or less, 24% by mass or less, 23% by mass or less, 22% by mass or less, 21% by mass or less, or 20% by mass or less.

[0031] Tinea versicolor is a mild fungal infection that occurs in the epidermis, causing discolored, scaly patches. It is commonly seen in young adults and usually has no other symptoms (Non-Patent Document 2). Since the causative fungus is the genus Malassezia, such as Malassezia furfur (Non-Patent Document 2) and Malassezia globasa (Non-Patent Document 5) (Non-Patent Documents 1, 3, 6), it is believed that suppressing the number of Malassezia fungi in the body can contribute to the prevention or improvement of tinea versicolor. Therefore, this agent can be used for preventing or improving tinea versicolor.

[0032] Seborrheic dermatitis (seborrheic eczema) is a chronic inflammation of the scalp, face, hairline, around the ears, and sometimes other areas that causes itching, greasy yellow scales, and dandruff (Non-Patent Document 8: Merck & Co., Inc., Kenilworth, NJ, USA, MSD Manual Home Edition, 17. Skin Disorders, Itching and Dermatitis, Seborrheic Dermatitis, Author: Mercedes E. Gonzalez, Medically Reviewed March 2018, [Retrieved January 31, 2023], Internet <URL: https: / / www.msdmanuals.com / ja-jp / %E3%83%9B%E3%83%BC%E3%83%A0 / 17-%E7%9A%AE%E8%86%9A%E3%81%AE%E7%97%85%E6%B0%97 / %E3%81%8B%E3%82%86%E3%81%BF%E3%81%A8%E7%9A%AE%E8%86%9A%E7%82%8E / %E8%84%82%E6%BC%8F%E6%80%A7%E7%9A%AE%E8%86%9A%E7%82%8E?query=%E8%84%82%E6%BC%8F%E6%80%A7%E7%9A%AE%E8%86%9A%E7%82%8E> ). Dandruff is said to be a milder form of seborrheic dermatitis (Non-Patent Document 6). Malassezia fungi are considered to be causative bacteria of seborrheic dermatitis and dandruff (Non-Patent Documents 1, 5, 6) or aggravating factors (Non-Patent Documents 3, 7, 8), and shampoos containing miconazole nitrate, which is effective against Malassezia fungi, and topical ketoconazole preparations (antifungal drugs) are used for treatment (Non-Patent Documents 5, 8). Therefore, if the number of Malassezia fungi in the living body can be suppressed, it is thought that this can contribute to the prevention or improvement of seborrheic dermatitis and dandruff. Therefore, this agent can be used for preventing or improving seborrheic dermatitis and dandruff.

[0033] Malassezia folliculitis is an infectious disease in which Malassezia fungi grow in pores and cause inflammation, resulting in papules, pimples, and itching, and is often seen on the trunk and upper arms (Non-Patent Document 7). Since Malassezia fungi are believed to be the causative fungus (Non-Patent Documents 3, 5, 6), it is believed that suppressing the number of Malassezia fungi in the body can contribute to the prevention or improvement of Malassezia folliculitis. Therefore, this agent can be used for preventing or improving Malassezia folliculitis.

[0034] Atopic dermatitis (AD) is a chronic inflammatory disease of the skin that occurs due to the complex involvement of genetic susceptibility, immune and epidermal barrier dysfunction, and environmental factors. Itching is the main symptom, and skin lesions range from mild erythema to severe lichenification. It has been reported that in adult AD, the detection rate of Malassezia-specific IgE high titers is high and the positive rate of prick tests is also high, the amount of bacteria is high in the lesions of AD, the degree of the rash is proportional to the specific IgE antibody titer, and there are cases where the rash improves with antibacterial therapy such as itraconazole (Non-Patent Document 3). It has also been reported that secretory proteins of Malassezia fungi cause sweat allergy in AD patients (Non-Patent Document 4). For these reasons, Malassezia fungi are considered to be an aggravating factor of AD (Non-Patent Documents 3, 4, 5), and it is thought that if the number of Malassezia fungi in the body can be suppressed, it can contribute to the improvement of AD. Therefore, this agent can be used for improving atopic dermatitis.

[0035] Malassezia otitis externa is an infectious disease caused by the proliferation of Malassezia fungi in the ear canal, resulting in inflammation accompanied by itching, and is common in animals such as dogs. Treatment involves ear irrigation and administration of antifungal drugs (ear drops and oral medications). Since Malassezia fungi are believed to be the causative fungus (Non-Patent Document 7), it is believed that suppressing the number of Malassezia fungi in the body can contribute to the prevention or improvement of Malassezia otitis externa. Therefore, this agent can be used to prevent or improve Malassezia otitis externa.

[0036] The present invention will be described below based on examples. It should be noted that the technical scope of the present invention is not limited to the characteristics shown in these examples. EXAMPLES

[0037] <Test Method> (1) Test substance The test substances used are shown in Table 1. [Table 1]

[0038] (2) Strains The following two species of fungal strains from the genus Malassezia were used. Malassezia furfur JCM9199(=ATCC?14521 =CBS?1878 =DBVPG?6825 =IFO?0656 =NBRC?0656) (hereinafter referred to as "M. furfur") Malassezia restricta NBRC103918(=ATCC 96801=CBS 7877=IFM 55992)(hereinafter referred to as "M. restricta")

[0039] (3) Culture medium The following media were used: Leening & Notman (LN) agar medium; peptone 1 (w / v), glucose 0.5 (w / v), yeast extract 0.01 (w / v), bovine bile 0.8 (w / v), glycerol 0.01 (w / v), glycerol monostearate 0.05 (w / v), polyoxyethylene sorbitan monostearate (Tween 60) 0.05 (w / v), milk 1.0 (w / v), agar 1.2 (w / v), LN liquid medium: LN agar medium except that agar is removed. Test substance-containing medium: LN liquid medium to which the test substance was added so that the final concentration was 2.5 (w / v)%, 5 (w / v)%, or 10 (w / v)%.

[0040] The sources of the reagents contained in the medium are as follows: Peptone, yeast extract: Becton Dickinson. Glucose, bovine bile, glycerol, glycerol monostearate, agar: Fujifilm Wako Pure Chemical Industries. Tween60:Tokyo Chemical Industry Co., Ltd. Milk: "Meiji Delicious Milk" Meiji.

[0041] (4)Culture M. furfur and M. restricta were spread on LN agar medium and cultured stationarily at 32°C for 3 days. The cultured cells were suspended in 3mL of LN liquid medium and cultured with shaking at 32°C and 210 revolutions per minute (rpm) for 24 hours, which was used as the preculture solution. 0.6mL of medium containing the test substance was dispensed into a 96-well deep plate. As a control, 0.6mL of LN liquid medium without the test substance was also dispensed into a 96-well deep plate. 20μL of the preculture solution was inoculated into each well and cultured with shaking at 32°C and 1000 rpm for 48 hours, which was used as the main culture solution.

[0042] (5) Measurement of bacterial cell concentration The bacterial cell concentration of the main culture solution was measured by the turbidity method. Specifically, 180 μL of water was dispensed into a 96-well flat-bottom plate, and 20 μL of the main culture solution was added to prepare a 10-fold diluted solution. The turbidity (OD ) of this diluted solution was measured by detecting the transmitted light intensity at 660 nm using a microplate reader (SpectraMax (registered trademark) M2, Molecular Devices). 660 The same test was carried out four times, and the average value and standard deviation were calculated.

[0043] <Example 1> Study of active ingredients 1 The test substances were erythritol, xylitol, mannitol and sorbitol (white powder), and the tests were performed according to the methods described in test methods (2) to (5). The bacterial strains used were M. furfur and M. restricta. The concentrations of the test substances in the medium containing the test substances were 10.0 (w / v)% for M. furfur and 5.0 (w / v)% for M. restricta. The turbidity of M. furfur is shown in Figure 1, and the turbidity of M. restricta is shown in Figure 2.

[0044] As shown in Figure 1, M. furfur had significantly lower turbidity when erythritol and xylitol were used as test substances compared to when no test substance was used, whereas when mannitol and sorbitol were used as test substances, the turbidity was only slightly lower compared to when no test substance was used.

[0045] In addition, as shown in Figure 2, M. restricta had significantly lower turbidity when erythritol and xylitol were used as test substances compared to when no test substance was used, whereas when mannitol and sorbitol were used as test substances, the turbidity was equivalent to that when no test substance was used.

[0046] These results demonstrated that erythritol and xylitol can inhibit the growth of fungi of the genus Malassezia.

[0047] <Example 2> Study of active ingredients 2 The test substances used were glycerol, medium sugar content reduced starch syrup, medium sugar content reduced starch syrup, and low sugar content reduced starch syrup, and the tests were carried out according to the methods described in test methods (2) to (5). The strain used was M. furfur. The concentration of the test substance in the medium containing the test substance was 2.5 (w / v)%. The results of the turbidity measurements are shown in Figure 3.

[0048] As shown in Figure 3, M. furfur showed a significantly lower turbidity only when medium-saccharified reduced starch syrup was used as the test substance, compared to when no test substance was used. This result demonstrated that medium-saccharified reduced starch syrup can inhibit the growth of Malassezia fungi.

Claims

1. A fungal agent for inhibiting the number of Malassezia fungi, containing one or more of the following (a) to (d) as an active ingredient; (a) Erythritol, (i) Xylitol, (c) Reduced starch syrup in which the sugar composition is less than 30% by mass of monosaccharides and less than 50% by mass of pentasaccharides or more. (e) Reduced starch syrup obtained by reducing starch syrup with a dextrose equivalent of 30 or more and 50 or less.

2. An agent containing one or more of the following (a) to (d) as an active ingredient, for preventing or improving one or more diseases selected from dandruff, tinea versicolor, seborrheic dermatitis, Malassezia folliculitis, atopic dermatitis, and Malassezia otitis externa; (a) Erythritol, (i) Xylitol, (c) Reduced starch syrup in which the sugar composition is less than 30% by mass of monosaccharides and less than 50% by mass of pentasaccharides or more. (e) Reduced starch syrup obtained by reducing starch syrup with a dextrose equivalent of 30 or more and 50 or less.

3. The agent according to claim 1 or claim 2, which is an external preparation.

4. The agent according to claim 1 or claim 2, selected from cosmetics, quasi-drugs, pharmaceuticals and sanitary products.

5. A method for suppressing the number of Malassezia fungi (excluding methods of surgery, treatment, or diagnosis of humans), comprising the step of applying one or more of the following (a) to (d) to the surface of a human or animal body; (a) Erythritol, (i) Xylitol, (c) Reduced starch syrup in which the sugar composition is less than 30% by mass of monosaccharides and less than 50% by mass of pentasaccharides or more. (e) Reduced starch syrup obtained by reducing starch syrup with a dextrose equivalent of 30 or more and 50 or less.

6. A method for preventing or improving one or more diseases selected from dandruff, tinea versicolor, seborrheic dermatitis, Malassezia folliculitis, atopic dermatitis, and Malassezia otitis externa (excluding methods of surgery, treatment, or diagnosis of humans), comprising the step of applying one or more of the following (a) to (d) to the surface of the body of a human or animal; (a) Erythritol, (i) Xylitol, (c) Reduced starch syrup in which the sugar composition is less than 30% by mass of monosaccharides and less than 50% by mass of pentasaccharides or more. (e) Reduced starch syrup obtained by reducing starch syrup with a dextrose equivalent of 30 or more and 50 or less.

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