JP2008100971A - Antifungal agent, mold remover detergent, resin having antifungal effect, and mold suppression method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive antifungal agent, a resin having an antifungal effect, and a mold suppression method, which is effective against black molds growing in a bathroom, lavatory, etc., is biologically safe and does not damage fabrics such as clothes. <P>SOLUTION: Cysteine is used as an active ingredient imparting an antifungal effect. Propagation of molds can be prevented or controlled by mixing cysteine with the antifungal agent, a mold remover detergent, the resin, etc. and applying them to a moldy area. The antifungal agent, the mold remover detergent, the resin, etc. comprising cysteine are preferably used against molds belonging to genera Cladosporium, Alternaria, or Aureobasidium. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention has an antifungal agent, a mold cleaning agent, and an antifungal effect, which is particularly effective against black mold that is easily generated in humid places such as bathrooms and bathrooms and is known to discolor black. The present invention relates to a resin and a method for suppressing mold generation.

  In humid places such as bathrooms, dressing rooms, washrooms, and kitchens at home, black mold tends to be generated, and since it turns black, it is easily recognized visually, and is subject to washing and mold prevention. Such black mold is a fungus represented by microorganisms belonging to the genus Cladosporium, Alternaria, Aureobasidium, etc. Even if an agent is used, removal may be difficult.

  In general, chlorine-based detergents are used to disinfect black mold, but chlorine-based detergents are toxic to humans, are environmentally harmful, and generate harmful chlorine gas when mixed with acid. In addition, although it may cause rough hands and bruises on clothes, it exhibits a strong bactericidal effect, but its safety is very low.

As an example of the prior art showing cleaning and antifungal effects against black mold, for example, Patent Document 1 listed below discloses peroxo represented by the formula: MHSO ₅ (where M is an alkali metal) as an essential component. Disclosed is a detergent composition for a washing machine tub, comprising hydrogen sulfate and 100 to 600 parts by weight of a water-soluble carbonate per 100 parts by weight of the peroxomonosulfate. ing. And it is described that the said composition does not generate | occur | produce harmful gas, even if it mixes with an acidic detergent.

  Patent Document 2 below discloses a black mold control agent containing a 1,2,4-dithiazolidine derivative as an active ingredient. And it is described that a safe and effective black mold control agent can be provided by using the derivative as an active ingredient.

  Moreover, the following patent document 3 discloses a mold cleaning agent using a seaweed extract which is considered to be highly safe because it is a natural product.

Further, Patent Document 4 below discloses a coating composition comprising a finely divided transparent titanium oxide of 1 μm or less mixed with a resin emulsion. And it describes that the said composition is used for prevention of generation | occurrence | production of black mold, deodorization, disinfection, etc.
Japanese Patent Laid-Open No. 5-247496 JP-A-6-49050 Japanese Patent Laid-Open No. 6-179895 JP-A-9-157549

  However, the conventional techniques exemplified in the above-mentioned patent documents have problems such as being unsuitable for industrial use, high cost, low safety, and the like. It was not always satisfactory.

  Therefore, the object of the present invention is to prevent black mold generated in bathrooms, toilets, etc., is safe for living organisms, does not damage cloths such as clothes, and is inexpensive and has an antifungal agent, a mold cleaning agent, An object of the present invention is to provide a resin having an antifungal effect and a method for suppressing the generation of mold.

  The present inventors have conducted intensive research to solve the above-mentioned problems, and are toxic to Cladosporium cladosporioides, a kind of black mold, from substances that are harmless to the human body. As a result of searching for the substances to be shown, the present invention was completed by finding a strong growth inhibitory action on cysteine, which is an amino acid.

  That is, one of the present invention is a fungicide containing cysteine and / or a cysteine derivative as an active ingredient.

  According to the antifungal agent of the present invention, the active ingredient cysteine and / or cysteine derivative suppresses fungal germination, suppresses fungal mycelial division, or suppresses fungal biofilm formation. It can prevent or suppress the growth of mold by applying it to the place.

  In the antifungal agent of this invention, it is preferable that cysteine conversion density | concentration is 0.1-100 mass% in conversion of solid content. Further, it is preferably used for molds belonging to the genus Cladosporium, the genus Alternaria, or the genus Aureobasidium.

  Another aspect of the present invention is a mold cleaning agent characterized by containing the antifungal agent of the present invention.

  According to the mold cleaning agent of the present invention, by containing cysteine in the mold cleaning agent, at the time of cleaning, cysteine which is an active ingredient of mold prevention action is used as a cleaning object such as a cleaning object, brush, sponge, etc. Therefore, it is possible to suppress the occurrence of mold on the object to be cleaned and the cleaning tool after cleaning. In addition, unlike chlorine-based cleaning agents, no harmful gas is generated, and it is difficult to cause rough hands and clothes.

  In the mold cleaning agent of the present invention, the cysteine equivalent concentration is preferably 0.1 to 100% by mass in terms of solid content.

  Still another of the present invention is a resin having an antifungal effect characterized by containing the antifungal agent of the present invention.

  According to the resin having an antifungal effect of the present invention, it is an active ingredient having an antifungal effect on a resin used in a place where mold tends to grow, such as joints and packing around water, such as a bathroom, a washroom, a kitchen, and a toilet. By containing cysteine, it is possible to prevent mold from being generated on the surface or inside thereof.

  In the resin having an antifungal effect of the present invention, the cysteine equivalent concentration is preferably 10 to 50% by mass. Moreover, the resin having an antifungal effect of the present invention is a resin composition comprising one or more selected from silicone resins, acrylic resins, vinyl acetate resins, and epoxy resins. It is preferable.

  On the other hand, the method for inhibiting the occurrence of mold according to the present invention is characterized by applying the fungicide according to the present invention.

  According to the method for inhibiting the occurrence of mold according to the present invention, safe and inexpensive cysteine that has already been widely used industrially is used as an active ingredient for antifungal action. Mold generation can be suppressed without damaging the fabric. In addition, no harmful gas is generated even when mixed with chlorinated detergents or acidic detergents.

  The mold generation suppressing method of the present invention can be preferably applied to molds belonging to the genus Cladosporium, the genus Alternaria, or the genus Aureobasidium.

  According to the present invention, the active ingredient cysteine suppresses fungal germination, suppresses fungal hyphal division, or suppresses fungal biofilm formation. Breeding can be prevented or suppressed. Cysteine is a safe and inexpensive substance that has already been widely used industrially, so that it can be widely applied to antifungal agents, fungicides, and antifungal walls and packings.

  Cysteine used in the present invention is a cysteine that is a kind of amino acid, and may be either D-form or L-form, and may be racemic (DL-form), but naturally existing L-form. Is preferred. Cysteine is widely used as an industrial raw material or supplement for foods, feed additives, beauty, cosmetic materials, pharmaceuticals, etc., and the world annual production is estimated to be 1,500 tons. Industrially, cysteine is mainly produced by extraction from hair or feather acid hydrolyzate, or by a chemical enzyme method such as synthesis of cysteine from phosphoserine by cysteine synthase. In the present invention, such industrially produced and commercially available cysteine can be used as it is. Therefore, there is an advantage that it is easy to obtain and inexpensive.

  In the present invention, a cysteine derivative can also be used as an active ingredient. As the cysteine derivative used in the present invention, a cysteine derivative intended to act on cysteine is preferably used, and examples thereof include N-acetyl-cysteine, cysteine methyl ester, cysteine ethyl ester and the like. These cysteine derivatives bring about cysteine which is an active ingredient by being decomposed by a degrading enzyme such as fungal deacetylase or esterase.

  Cysteine or the cysteine derivative used in the present invention is an acid salt such as an inorganic acid salt such as hydrochloride, nitrate or acetate, an alkali metal salt such as sodium salt or potassium salt, or a magnesium salt or calcium salt. It may be in the form of a salt such as an alkaline earth metal salt.

  In the present invention, “cysteine-equivalent concentration” means the concentration of cysteine for cysteine, and the above-mentioned cysteine derivative is a theory that can be stoichiometrically obtained by decomposing the cysteine derivative with the decomposing enzyme or the like. Mean cysteine concentration.

  The antifungal agent of the present invention is cysteine, a cysteine derivative, or the like when preparing powders, blocks, creams, gels, solutions, pastes, suspensions / emulsions for aerosols, etc. according to known techniques. It can be obtained by blending salts. In this case, a simple composition in which only an active ingredient that brings about the above-mentioned cysteine in a solvent such as water, a buffer solution, or an emulsifying solvent can be used alone.

  Cysteine is easily water-soluble and can be easily mixed with many other compounds, so it can be used in a wide variety of forms such as powders, blocks, creams, gels, solutions, pastes, suspensions and emulsions for aerosols. Is possible.

  In the present invention, the cysteine concentration in the antifungal agent can be appropriately selected in light of the concentration of cysteine necessary for inhibiting mold growth, but preferably the cysteine equivalent concentration is 0.1 to 0.1 in terms of solid content. It is 100 mass%, More preferably, it is 0.5-100 mass%, More preferably, it is 1-100 mass%. In addition, for example, the blending ratio at the time of use when used in the form of a solution can be appropriately selected in view of their solubility, dispersibility, etc., but cysteine, cysteine derivatives, or salts thereof are cysteine. It is preferable to contain 0.05-10g per 100ml in conversion, and it is more preferable to contain 1-10g.

  The mold cleaning agent of the present invention can be obtained by blending cysteine, cysteine derivatives, or salts thereof when preparing the cleaning agent according to a known technique. In this case, it can also mix | blend with a commercially available cleaning agent etc.

  In the mold cleaning agent of the present invention, a surfactant or the like can be added as a component having a cleaning action. Further, an antibacterial component having an antibacterial action can be added. Moreover, you may use together the active ingredient currently used for the cleaning agent for conventional molds, such as a chlorine-type cleaning agent.

  Cysteine can exert its antifungal action even if it is mixed with a cleaning agent having a cleaning action or an antibacterial agent having an antibacterial action without reducing their effectiveness. In addition, unlike chlorine-based cleaning agents, no harmful gas is generated, and it is difficult to cause rough hands and clothes. Furthermore, even when an active ingredient of a conventional mold cleaning agent is used in combination, it is possible to reduce the amount of the chlorine-based active ingredient and the like, and to reduce the above-mentioned problems caused by the chlorine-based cleaning agent.

  In the present invention, the cysteine concentration in the mold cleaning agent can be appropriately selected in light of the concentration of cysteine necessary for mold growth inhibition, the concentration of other components such as components that bring about a cleaning action, The cysteine equivalent concentration is preferably 0.1 to 100% by mass in terms of solid content, more preferably 0.5 to 100% by mass, and even more preferably 1 to 100% by mass. In addition, for example, the blending ratio at the time of use when used in the form of a solution can be appropriately selected in view of their solubility, dispersibility, etc., but cysteine, cysteine derivatives, or salts thereof are cysteine. It is preferable to contain 0.05-10g per 100ml in conversion, and it is more preferable to contain 1-10g.

  The resin having an antifungal effect of the present invention can be obtained by blending cysteine, a cysteine derivative, or a salt thereof when preparing the resin according to a known technique.

  Preferred examples of the resin include a resin composition containing one or more selected from silicone resins, acrylic resins, vinyl acetate resins, and epoxy resins. The active ingredient that brings about the cysteine is blended in a preparation solution before the resin is molded and cured, and is encapsulated in the resin after the molding and curing.

  Cysteine has little influence on the curability and moldability of the resin even if it is used in the resin, and it can effectively exert its fungicidal action, so it can be used in bathrooms, toilets, kitchens, toilets, etc. By compounding with various resins such as resin used in mold-prone areas such as water joints and silicone in lunch box packing, it is possible to prevent mold from growing on the surface or inside thereof.

  In the present invention, the cysteine concentration in the resin having the antifungal effect can be appropriately selected in light of the concentration of cysteine necessary for inhibiting mold growth and the concentration of other components such as a resin component and a crosslinking agent. However, the cysteine equivalent concentration is preferably 10 to 50% by mass, and more preferably 30 to 50% by mass.

  On the other hand, in the method for inhibiting mold generation according to the present invention, the application means is not particularly limited. For example, the occurrence of mold is prevented by means such as coating, spraying, spraying, or encapsulating in an antibacterial material in advance. Cysteine, a cysteine derivative, or a salt thereof is applied to a place where suppression is desired or where mold is growing.

  For example, in the case of a wall of a building or bathroom, it is performed by means such as direct spraying or mixing with a paint and painting as a coating agent. In addition, as described above, by containing cysteine in the mold cleaning agent, when cleaning, cysteine, which is an active ingredient of the mold prevention action, is distributed to cleaning objects such as cleaning objects, brushes, sponges, and the like. Therefore, it can be expected to suppress the occurrence of mold on the object to be cleaned and the cleaning tool after cleaning.

The application rate can be appropriately selected according to the type of mold, the material of the application site, the surface properties, etc. According to the test examples described below, it is preferably about 1 to 100,000 mg per 1 m ² , More preferably, it is about 100 to 10,000 mg per 1 m ² . If the application amount is too small, a sufficient control effect cannot be expected, and cysteine has a peculiar smell.

  There is no particular limitation on the type of mold to which the present invention is applied, but Cladosporium is a black mold that tends to occur in damp places such as bathrooms, dressing rooms, toilets, and kitchens at home. It can be preferably used for molds belonging to microorganisms of the genera, genus Alternaria and genus Aureobasidium.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but these examples do not limit the scope of the present invention.

  Cladosporium cladosporioides NRBC4457 (hereinafter referred to as C. cladosporioides) used in the following test examples was purchased from National Institute of Technology and Evaluation. This bacterium was statically cultured in a potato dextrose medium at 27 ° C., and C. cladosporioides spores formed on the surface of the culture solution and collected on the biofilm were collected and used in the following experiments.

  Cysteine was purchased from Sigma Aldrich Japan.

<Test Example 1> Germination suppression test
C. cladosporioides spores were suspended in a potato dextrose medium to prepare a suspension of 4 × 10 ⁴ (cells / ml). Cysteine was added to this suspension so that the final concentrations were 10, 1, 0.1, and 0.01 mg / ml, and stationary culture was performed at 27 ° C. Turbidity (OD620 nm) was measured at 24 and 48 hours after the start of culture, and the number of bacteria was shown as turbidity.

  As a result, as shown in FIG. 1, the growth of C. cladosporioides was remarkably suppressed in a concentration-dependent manner. On the third day of the culture, the growth inhibitory effect of C. cladosporioides by cysteine was confirmed by visual observation (FIG. 2). From these results, it was revealed that cysteine has an inhibitory effect on germination of C. cladosporioides.

<Test Example 2> Hyphal division inhibition test
C. cladosporioides spores were suspended in a potato dextrose medium to prepare a suspension of 4 × 10 ⁴ (cells / ml). This suspension was subjected to static culture at 27 ° C. for 24 hours to germinate all of the spore cells and induce mycelial division. Cysteine was added to final concentrations of 10, 1, and 0.1 mg / ml, and static culture was further performed at 27 ° C. Turbidity (OD 620 nm) was measured 24 hours after the addition of cysteine, and the number of bacteria was shown as turbidity.

  As a result, as shown in FIG. 3, in the cysteine addition group, the growth of C. cladosporioides was suppressed in a concentration-dependent manner. From this result, it was revealed that cysteine has a C. cladosporioides hyphal division inhibitory effect.

<Test Example 3> Biofilm formation inhibition test
C. cladosporioides spores were suspended in a potato dextrose medium to prepare a suspension of 4 × 10 ⁴ (cells / ml). 1 ml of this suspension is dispensed onto a 24-well plastic plate (manufactured by NUNK), added to each well so that the final concentrations of cysteine are 5, 0.5 and 0.05 mg / ml, respectively, and left at 27 ° C. Culture was performed. On the seventh day from the start of the culture, the biofilm formed on the surface of the culture solution was collected and the wet weight was measured. In addition, the biofilm is immersed in 1 ml of Sabouraud medium, to which Alamar blue (a reagent for measuring living cells, manufactured by Cellotec Co., Ltd.) is added, and the color change (blue to red) after culturing for 5 hours is measured with the absorbance value OD540nm and absorbance. It was quantified as the difference from the value OD620nm.

  As a result, as shown in FIG. 4, the amount of biofilm formed was significantly reduced by the addition of cysteine, and it was clarified that the addition of cysteine suppressed biofilm formation. In addition, when Alamar blue was used to measure the metabolic capacity of the number of viable bacteria contained in the biofilm, the change in color tone was suppressed in the cysteine added group as shown in FIG. 5, and the metabolism of C. cladosporioides by cysteine was suppressed. It was suggested that the ability to form biofilms decreased with the decrease in function.

<Test Example 4> C. cladosporioides growth confirmation test on cysteine-containing agar medium
A potato dextrose agar medium containing cysteine (1 mg / ml) was prepared, C. cladosporioides spores (4 × 10 ⁴ cells) were transplanted on the surface, and after standing at 27 ° C. for 3 days or 7 days, growth The condition was observed.

  As a result, as shown in FIG. 6, it was revealed that C. cladosporioides is difficult to grow on the cysteine-containing agar surface, and that cysteine is effective in preventing C. cladosporioides from adhering to and growing on the solid surface. It was.

<Test Example 5> C. cladosporioides growth test on cysteine-containing silicone
C. cladosporioides is a kind of black mold that occurs frequently in humid places such as bathrooms and toilets, but since cysteine can suppress this growth, it contains cysteine in silicone used as a filler for bathroom wall joints. The growth state of C. cladosporioides was observed. Viscoke N (made by Cemedine Co., Ltd .; viscous with silicone-based filler, but gradually solidifies when left in the air) is mixed with cysteine so that the mass% is 50, 10 and 5%, and 24 hours at room temperature Let it stand and harden. The solidified silicone was subjected to high-pressure steam sterilization at 121 ° C. for 20 minutes, and then used for the experiment.

C. cladosporioides spores were suspended in a potato dextrose medium to prepare a suspension of 4 × 10 ⁴ (cells / ml). 1 ml of this suspension was dispensed onto a 24-well plastic plate (manufactured by Nunk), and various cysteine-containing silicones were immersed in each well, followed by stationary culture at 27 ° C., and the growth state of C. cladosporioides was observed.

  As a result, as shown in FIG. 7, the growth of C. cladosporioides was suppressed in the medium soaked with cysteine-containing silicone. Moreover, the silicone surface not containing cysteine was covered with C. cladosporioides biofilm, but the formation of biofilm was also significantly suppressed by adding cysteine (FIG. 8).

  Based on the above results, it is considered that cysteine can function as an antifungal factor that is safe for the human body, and it can be added to antifungal agents and fungicides, or to the joints of bathrooms, packing parts of water bottles and lunch boxes. It was shown that the occurrence of black mold is suppressed.

<Production Example 1>
Each raw material was mixed by the mixing | blending of following Table 1, and the antifungal agent was prepared.

  This antifungal agent was good in usability without worrying about the odor of cysteine.

<Production Example 2>
Each raw material was mixed according to the formulation shown in Table 2 to prepare a mold cleaning agent.

  This mold cleaning agent did not mind the odor of cysteine and was good in use feeling.

It is a graph which shows the influence which it has on C. cladosporioides germination by cysteine. It is a photograph which shows the germination state of the culture | cultivation 3rd day of C. cladosporioides cultured with the cysteine containing medium. It is a graph which shows the influence which it has on C. cladosporioides hyphal division by cysteine. It is a graph which shows the influence which it has on the biofilm formation ability of C. cladosporioides by cysteine by the comparison of wet weight. It is a graph which shows the influence which it has on the biofilm formation ability of C. cladosporioides by a cysteine by the comparison of the measured value by the Alamar Blue method. It is a photograph which shows C. cladosporioides growth property on a cysteine containing potato dextrose agar medium. It is a photograph which shows C. cladosporioides growth property in the culture | cultivation day in the culture medium which soaked the cysteine compounding silicone. It is a photograph which shows C. cladosporioides growth property on the cysteine mixing | blending silicone in the culture | cultivation 25th day.

Claims (10)

  An antifungal agent containing cysteine and / or a cysteine derivative as an active ingredient.   The antifungal agent according to claim 1, wherein the cysteine equivalent concentration is 0.1 to 100% by mass in terms of solid content.   The antifungal agent according to claim 1 or 2, which is used against molds belonging to the genus Cladosporium, the genus Alternaria, or the genus Aureobasidium.   A mold cleaning agent comprising the mold prevention agent according to any one of claims 1 to 3.   The mold cleaning agent according to claim 4, wherein the concentration in terms of cysteine is 0.1 to 100% by mass in terms of solid content.   A resin having an antifungal effect, comprising the antifungal agent according to any one of claims 1 to 3.   The resin having an antifungal effect according to claim 6, wherein the concentration in terms of cysteine is 10 to 50% by mass.   The resin having an antifungal effect according to claim 6 or 7, which is a resin composition comprising one or more selected from silicone resins, acrylic resins, vinyl acetate resins, and epoxy resins. .   The mold | generation prevention | control method characterized by administering the mold inhibitor as described in any one of Claims 1-3.   The method according to claim 9, which is used for molds belonging to the genus Cladosporium, the genus Alternaria, or the genus Aureobasidium.