TW201815286A - Disinfectant - Google Patents

Abstract

Provided is a disinfectant containing an [alpha],[beta]-unsaturated aldehyde represented by general formula (1) as an active ingredient (wherein: R1-R3 each independently represent a hydrogen atom, an alkyl group having 1-10 carbon atoms, an alkenyl group having 2-10 carbon atoms, or an aryl group having 6-12 carbon atoms; R1 may be bonded with R2 or R3 to form an alkylene group having 2-6 carbon atoms; and R1 and R2 would not simultaneously be hydrogen atoms).

Description

   Fungicide   

This invention relates to bactericides.

In recent years, in the excavation of fossil fuels (such as oil, natural gas, shale oil, shale gas, etc.), high-pressure water is used to break the rock disk, and biological corrosion is seen in the iron pipes of the high-pressure water flow path. Biological corrosion refers to the corrosion phenomenon caused directly or indirectly by the action of microorganisms present in the environment; although several research cases have been reported (for example, non-patent document 1 etc.), the mechanism of the occurrence still remains. There are unexplained parts. In recent studies, it has been reported that biocorrosion is caused by two or more microorganisms (for example, sulfate-reducing bacteria and methanogens, etc.), and the effects of these microorganisms may sometimes multiply promote corrosion. As an effective ingredient for sterilizing these microorganisms, acrolein and the like have been conventionally known (see Patent Document 1). In addition, in the SPE Annual Technical Conference and Exhibition SPE 146080 held in Denver, Colorado, USA from October 30 to November 2, 2011, acrolein was also sterilized against microorganisms. However, acrolein is a compound that is highly toxic and whose concentration is strictly controlled in terms of labor safety and environmental safety, and there are so-called problems that require attention in handling. Furthermore, the point that acrolein is extremely easy to polymerize and lacks thermal stability, or lacks pH stability, and the amount gradually decreases due to the pH of the environment in which it is used, also poses a problem in operation.

    [Prior technical literature]         [Patent Literature]    

[Patent Document 1] US Patent No. 2987475

    [Non-patent literature]    

[Non-Patent Document 1] Journal of Bioscience and Bioengineering VOL. 110, No. 4, pp. 426-430 (2010)

[Non-Patent Document 2] SPE Annual Technical Conference and Exhibition SPE 146080, 2011; http://dx.doi.org/10.2118/146080-MS

As described above, when acrolein is used as a bactericidal compound, there are problems in terms of safety, stability, and pH stability, and a safer and more stable compound is expected to be substituted. Therefore, an object of the present invention is to provide a fungicide having an active ingredient having high thermal stability and high pH stability, and excellent bactericidal properties.

According to the present invention, the above-mentioned objects can be achieved by the following [1] to [7].

[1] A bactericide containing an α, β-unsaturated aldehyde (hereinafter, referred to as an aldehyde (1)) as an active ingredient represented by the following general formula (1).

(R ¹ to R ³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms; however, R ¹ may be different from R ² or R ^{3 is} connected to each other to form an alkylene group having 2 to 6 carbon atoms, and R ¹ and R ^{2 are} not hydrogen atoms at the same time).

[2] The fungicide according to [1], wherein R ¹ to R ³ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

[3] The fungicide according to [1] or [2], wherein R ³ is a hydrogen atom.

[4] The germicidal agent according to any one of [1] to [3], which is used to inhibit biological corrosion of metals.

[5] A method for sterilization, wherein the germicidal agent according to any one of [1] to [4] is used.

[6] A method for inhibiting biological corrosion of a metal, wherein the fungicide according to any one of [1] to [4] is used.

[7] The use of the fungicide according to any one of [1] to [4], which is used to inhibit biological corrosion of metals.

The agent of the present invention has excellent bactericidal properties by containing aldehyde (1).

In particular, the agent of the present invention has the advantages of so-called extremely low toxicity, high thermal stability, and high pH stability compared with the previous fungicide containing acrolein. Although the reason may not be clear, it is judged that the aldehyde (1) has at least one alkyl, alkenyl or aryl group at the β position, and compared with acrolein without a substituent at the β position, it is more effective for living molecules or growing chains. The behavior of the β-position addition reaction of such large molecules will have different effects.

FIG. 1 is a graph showing the pH stability of senecioaldehyde (SAL).

Fig. 2 is a graph showing pH stability of acrolein.

    [Form of Implementing Invention]    

The agent of the present invention is characterized by containing an aldehyde (1) as an active ingredient.

In the aldehyde (1), R ¹ to R ³ each independently represent an alkyl group having 1 to 10 carbon atoms, which may be linear, branched, or cyclic. Examples include methyl and ethyl. , N-propyl, isopropyl, n-butyl, isobutyl, tertiary butyl, n-pentyl, n-hexyl, n-octyl, n-decyl, n-dodecyl, cyclopentyl and the like. From the standpoint of bactericidal properties, methyl, ethyl or n-propyl is more preferred, methyl or ethyl is more preferred, and methyl is even more preferred.

R ¹ to R ³ each independently represent an alkenyl group having 2 to 10 carbon atoms, which may be linear, branched, or cyclic. Examples include vinyl, allyl, and 1-pentene. -1-yl, 4-methyl-3-penten-1-yl, 4-penten-1-yl, 1-hexene-1-yl, 1-octen-1-yl, 1-decene -1-yl, etc. Among them, an alkenyl group having 1 to 8 carbon atoms is more preferable, and an alkenyl group having 1 to 6 carbon atoms is more preferable.

R ¹ to R ³ each independently represent an aryl group having 6 to 12 carbon atoms, and examples thereof include phenyl, tolyl, ethylphenyl, xylyl, trimethylphenyl, naphthyl, and biphenyl Wait. Among them, an aryl group having 6 to 10 carbon atoms is more preferable.

In addition, when R ¹ and R ² or R ^{3 are} connected to each other to represent an alkylene group having 2 to 6 carbon atoms, examples of the alkylene group include ethylene, propyl, butyl, and butyl. N-pentyl, n-hexyl, 2-methyl-n-ethyl, 1,2-dimethyl-n-ethyl, 2-methyl-n-propyl, 2,2-dimethyl-n-propyl, 3- Methyl-n-pentyl and the like.

R ¹ to R ³ are each preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

From the viewpoint of ensuring bactericidal and thermal stability and pH stability of the terms to R ^1, R ² is at least one of which is methyl are preferred, in R ^1, R ² is more preferably simultaneously methyl.

From the same viewpoint, R ³ is preferably a hydrogen atom.

Examples of the aldehyde (1) include 2-butenal, 2-pentenal, 2-hexenal, 2-heptenal, 2-octenal, 2-nonenal, 2- Decenal, 2-undecenal, 2-dodecenal, 2-tridecenal, 4-methyl-2-pentenal, 4-methyl-2-hexenal, 5-methyl 2-Hexenal, 4,4-dimethyl-2-pentenal, 6-methyl-2-heptenal, 4-ethyl-2-hexenal, 2-methyl-2 -Butenal, 2-methyl-2-pentenal, 2-methyl-2-hexenal, 2-methyl-2-heptenal, 2-methyl-2-octenal, 4 -Methyl-2-propyl-2-hexenal, 2,4-dimethyl-2-pentenal, 2,4-dimethyl-2-hexenal, 2,4-dimethyl 2-heptenal, 2,5-dimethyl-2-hexenal, 2,6-dimethyl-2-heptenal, 2,4,4-trimethyl-2-pentenal , 2-ethyl-2-butenal, 2-ethyl-2-pentenal, 2-ethyl-2-hexenal, 2-ethyl-2-heptenal, 2-ethyl- 2-octenal, 2-ethyl-4-methyl-2-pentenal, 2-ethyl-4-methyl-2-hexenal, 2-propyl-2-butenal, 2 -Propyl-2-pentenal, 2-propyl-2-hexenal, 2-propyl-2-heptenal, 2-propyl-4-methyl-2-pentenal, 2- Propyl-5-methyl-2-hexenal, 2-isopropyl-2-butene , 2-isopropyl-4-methyl-2-pentenal, 2-isopropyl-4-methyl-2-hexenal, 2-isopropyl-5-methyl-2-hexene Aldehyde, 2-butyl-2-butenal, 2-butyl-2-pentenal, 2-butyl-2-hexenal, 2-butyl-2-heptenal, 2-butyl 2-octenal, 2-isobutyl-2-heptenal, 2-isobutyl-6-methyl-2-heptenal, 2-pentyl-2-butenal, 2-pentyl 2-Pentenal, 2-pentyl-2-hexenal, 2-pentyl-2-heptenal, 2-pentyl-2-octenal, 3-methyl-2-butene Aldehyde, 3-methyl-2-pentenal, 3-methyl-2-hexenal, 3-methyl-2-heptenal, 3-methyl-2-octenal, 3-methyl 2-nonenal, 3-methyl-2-decenal, 3-methyl-2-undecenal, 3-methyl-2-dodecenal, 3-methyl-2-decenal Trienal, 3-ethyl-2-pentenal, 3,4-dimethyl-2-pentenal, 3,4,4-trimethyl-2-pentenal, 3-isopropyl 4-methyl-2-pentenal, 3-ethyl-2-hexenal, 3-propyl-2-hexenal, 3,5-dimethyl-2-hexenal, 3- (Tertiary butyl) -4,4-dimethyl-2-pentenal, 3-butyl-2-heptenal, 2,3-dimethyl-2-butenal, 2-ethyl 3-methyl-2-butenal, 2-isopropyl-3-methyl-2-butenal, 2,3-bis 2-Pentenal, 2,3,4-trimethyl-2-hexenal, 2-isobutyl-3-methyl-2-butenal, 3-methyl-2-pentyl 2-pentenal, 2,3-diethyl-2-heptenal, 2- (1,1-dimethylpropyl) -3-methyl-2-butenal, 3,5, 5-trimethyl-2-hexenal, 2,3,4-trimethyl-2-pentenal, 2-cyclopropylpropanal, 2-cyclopentylpropanal, 2-cyclomethylene Amylhexanoaldehyde, 2- (3-methylcyclopentylidene) propanal, 2-cyclohexylenepropanal, 2- (2-methylcyclohexylene) propanal, 2-cyclohexylenebutyraldehyde, 2-cyclohexylenehexanaldehyde, 1-methylfluorenylcyclobutene, 1-methylfluorenyl-3,3-dimethylcyclobutene, 1-cyclopropyl-2-methylcyclobutene, 1 -Formamylcyclopentene, 5-ethyl-1-formamylcyclopentene, 1-formamyl-3-methylcyclopentene, 1-formamyl-4-methylcyclopentene, 1-methylfluorenyl-5-methylcyclopentene, 1-methylfluorenyl-3,3-dimethylcyclopentene, 1-methylfluorenyl-4,5-dimethylcyclopentene, 1- Formamyl-2-methylcyclopentene, 1-methylfluorenyl-5-isopropyl-2-methylcyclopentene, 1-methylfluorenyl-2,5,5-trimethylcyclopentene , 1-methylfluorenylcyclohexene, 1-methylfluorenyl-3-methylcyclohexene, 1-methylfluorenyl-4-methylcyclohexene, 1-methylfluorenyl-5-methyl Hexene, 1-methylfluorenyl-6-methylcyclohexene, 1-methylfluorenyl-3,3-dimethylcyclohexene, 1-methylfluorenyl-5,5-dimethylcyclohexene , 1-methylfluorenyl-2 methylcyclohexene, 1-methylfluorenyl-2,5,6,6-tetramethylcyclohexene, 1-methylfluorenyl-2,4,6,6-tetramethylene Methylcyclohexene, 1-methylfluorenylcycloheptene, 1-methylfluorenyl-2-methylcycloheptene, 1-methylfluorenyl-3-methylcycloheptene, 1-methylfluorenylcyclooctene Alkenes, 2,4-pentadienal, 2,4-hexadienal, 2,5-hexadienal, 5-methyl-2,4-hexadienal, 2,4-heptadiene Aldehyde, 2,4-octadienal, 2,7-octadienal, 3,7-dimethyl-2,6-octadienal (citral), 2,4,6-octatriene Aldehyde, 7-methyl-2,4,6-octatrienal, 2,4-nonadienal, 2,6-nonadienal, 4,8-dimethyl-2,7-nonane Enal, 2,4-decadienal, 2,4-undecadienal, 2,4-dodecadienal, 2,4-tridecadienal, 2,4,7 -Thirteen carbon trienal, 3-phenyl acrolein, 3-phenyl-2-methacryl, 3- (o-tolyl) acrolein, 3- (p-tolyl) acrolein, 3-naphthalene Acrolein, etc. Among them, 3-methyl-2-butenal, 3-methyl-2-pentenal, 3-methyl-2-hexenal, 3-ethyl-2-pentenal, 3- Ethyl-2-hexenal and 3-propyl-2-hexenal are preferred, and 3-methyl-2-butenal, 3-methyl-2-pentenal, and 3-ethyl 2-Pentenal is more preferred, and 3-methyl-2-butenal (senecioaldehyde, hereinafter simply referred to as SAL) is even more preferred.

In addition, as for a compound having a trans isomer and a cis isomer, either one or a mixture may be used. When a mixture is used, any mixing ratio may be used.

The aldehyde (1) can be a commercially available product, or it can be synthesized by an oxidative dehydrogenation reaction of a corresponding α, β-unsaturated alcohol (see, for example, Japanese Patent Application Laid-Open No. 60-224652).

In addition to the aldehyde (1), the agent of the present invention may further contain components conventionally used in the field of fungicides as long as the object of the present invention is not impaired. Examples of the ingredients include other bactericides, antibacterial agents, dispersants, suspending agents, spreading agents, penetrating agents, wetting agents, pastes, stabilizers, flame retardants, colorants, antioxidants, and anti-oxidants. Static agents, foaming agents, lubricants, gelling agents, film-forming aids, antifreeze agents, viscosity adjusters, pH adjusters, preservatives, emulsifiers, defoamers, carriers, etc.

Examples of other fungicides include oxidants (peracetic acid, potassium monopersulfate, sodium perborate, hydrogen peroxide, sodium percarbonate, etc.), phosphonium salts (THPS, polyether polyaminomethylene phosphonic acid) Salt, tributyltetradecylphosphonium chloride, etc.), alkylbenzenesulfonic acid, 4th ammonium salt (N-alkyldimethylbenzyl ammonium chloride, N-dialkylmethylbenzyl ammonium chloride Etc.), isothiazoline, thiazoline, isothiazolone compounds (2- (thiocyanomethylthio) benzothiazole, isothiazolone, etc.), thiocarbamate compounds, hydroquinone compounds Aldehyde compounds other than aldehyde (1) (glutaraldehyde, chloroacetaldehyde, 1,9-nonanedial, 2-methyl-1,8-octanedial, 3-methylglutaraldehyde, etc.), even Nitrogen compounds, benzalconium chloride, hypochlorous acid, Amidazine compounds, imidazole compounds (1,2-dimethyl-5-nitro-1H-imidazole, etc.), amino alcohols, ethers, liposomes, alkynes, bromine biocides (2 , 2-dibromo-2-nitroacetamidine, etc.), aldehydes (endo-β-1,2-galactanase, etc.), metal ions, phenolic compounds, and the like. These fungicides can be used alone or in combination of two or more.

Examples of dispersants include interfacial activities such as sulfates of higher alcohols, alkylsulfonic acids, alkylarylsulfonic acids, hydroxyalkylamines, fatty acid esters, polyalkylene oxides, and sorbitans. Agents; soaps, casein, gelatin, starch, alginic acid, agar, carboxymethyl cellulose (CMC), polyvinyl alcohol, pine root oil, sugar oil, bentonite, cresol soap, etc. These dispersants may be used alone or in combination of two or more.

Examples of the carrier include water, alcohols (methanol, ethanol, isopropanol, glycol, glycerin, etc.), ketones (acetone, methyl ethyl ketone, etc.), and aliphatic hydrocarbons (hexane, flowing paraffin, etc.) , Aromatic hydrocarbons (benzene, xylene, etc.), halogenated hydrocarbons, amines, esters, nitriles and other liquid carriers; clays (kaolin, bentonite, acid clay, etc.), talc (talc, wax powder, etc.), Silica (diatomite, anhydrous silicic acid, mica powder, etc.), alumina, sulfur powder, activated carbon and other solid carriers. These carriers may be used alone or in combination of two or more.

The total content ratio of the aforementioned active ingredients in the agent of the present invention can be appropriately set depending on the dosage form or the use state, etc., but it is usually 1 to 99.9% by mass. From the viewpoint of cost and effect, it is preferably 5 to 99.9% by mass, more preferably 5 to 95% by mass.

The method for producing the agent of the present invention is not particularly limited, and a known method or a method based on it can be adopted. For example, it can be manufactured by adding and mixing the usual components in the fungicide field as needed in the aldehyde (1).

Examples of the dosage form of the present invention include emulsions, liquids, aqueous solvents, hydration agents, powders, granules, granules, lozenges, pastes, suspensions, sprays, coating agents and the like. There is no particular limitation on the method of formulating into each dosage form, and the method can be formulated by a known method or a method based on it.

The aldehyde (1), which is an active ingredient of the present invention, has a bactericidal effect on microorganisms. There are no particular restrictions on the microorganisms to which the agent of the present invention is applied, and examples include coliforms, bacillus, salmonella, veterans, vibrio, staphylococcus, streptococcus, enterococcus, anthracnose, botulinum, tetanus Such as the microorganisms found in ordinary living environment, or sulfate reducing bacteria, nitrate reducing bacteria, methanogenic bacteria, iodine oxidizing bacteria, iron oxidizing bacteria and sulfur oxidizing bacteria and other microorganisms that can cause biological corrosion of metals. Since the aldehyde (1) has so-called low toxicity, high thermal stability and high pH stability, the agent of the present invention is suitable for the purpose of inhibiting biological corrosion of metals. In addition, the "inhibition" of biological corrosion in the present invention refers to the concept of preventing biological corrosion in advance and inhibiting the progress (deterioration) of biological corrosion.

The aforementioned "sulfate-reducing bacteria" refers to a general term for microorganisms having the ability to reduce sulfates. Specific examples of the sulfate-reducing bacteria include microorganisms of the genus Desulfovibrio, microorganisms of the genus Desulfobacter, and microorganisms of the genus Desulfotomaculum.

The aforementioned "nitrate-reducing bacteria" refers to a general term for microorganisms capable of reducing nitrate.

The aforementioned "methanogenic bacteria" refers to a general term for microorganisms that have the ability to generate methane in a toxic atmosphere. Specific examples of methanogens include microorganisms of the genus Methanobacterium, microorganisms of the genus Methanococcus, and microorganisms of the genus Methanosarcina.

The "iodine oxidizing bacteria" means having the iodide ion (I ^-) microorganisms oxidized to molecular iodine (I ₂₎ of the ability of a generic name. Specific examples of the iodine oxidizing bacteria include rose discoloration bacteria sp. 2S-5 and iodine oxidizing bacteria MAT3 strain.

The aforementioned "iron-oxidizing bacteria" refers to a general term for microorganisms that have the ability to oxidize divalent iron ions (Fe ²⁺ ) to trivalent iron ions (Fe ³⁺ ). Specific examples of the iron-oxidizing bacteria include Mariprofundus ferrooxydans, Acidithiobacillus ferrooxidans, and the like.

The aforementioned "sulfur-oxidizing bacteria" refers to a general term for microorganisms having the ability to oxidize sulfur or inorganic sulfur compounds. Specific examples of the sulfur-oxidizing bacteria include bacteria of the genus Thiobacillus, bacteria of the genus Acidithiobacillus, archaea of the genus Sulfolobus, and genus of Acidianus Archaea and so on.

When the agent of the present invention is used as a metal biological corrosion inhibitor, it is used to suppress at least one selected from the group consisting of sulfate reducing bacteria, nitrate reducing bacteria, methanogenic bacteria, iodine oxidizing bacteria, iron oxidizing bacteria and sulfur oxidizing bacteria Bio-corrosion is preferred; more preferably, it is used to inhibit bio-corrosion caused by at least one selected from the group consisting of sulfate-reducing bacteria, nitrate-reducing bacteria, and methanogen; Biocorrosion caused by at least one of them; particularly preferred for inhibiting biocorrosion caused by methanogens.

Methanogens like aerobic environments and grow in paddy fields, as well as in swamps, ponds, lakes, rivers, oceans and fossil fuel mining sites.

Sulfate-reducing bacteria like anaerobic environments, and will grow roughly in an environment with moisture, and grow in all places such as forest soils, dry fields, swamps, ponds, lakes, rivers and oceans.

Nitrate-reducing bacteria prefer an aerobic environment and can grow even in an oxidizing environment compared to methanogens or sulfate-reducing bacteria, so they grow in the above environment.

Iron oxidizing bacteria are present in mine wastewater. It also grows in rivers and other places where there is a little brown deposits.

Sulfur-oxidizing bacteria grow in the same environment as iron-oxidizing bacteria, and because they also grow in domestic drainage, they are also related to concrete corrosion in the sewer. Moreover, it also grows in sulfur-containing hot springs.

The place where iodine-oxidizing bacteria are mostly present is underground salt water, and it is also widely present in the marine environment.

Therefore, when the agent of the present invention is used as a metal biological corrosion inhibitor, it is suitably used for the purpose of suppressing the biological corrosion of a metal that is present in or placed in the living environment of the microorganism.

In the case where the agent of the present invention is used as a bio-corrosion inhibitor of a metal, the target metal is not particularly limited as long as it is exposed to the environment where microorganisms causing bio-corrosion exist. Examples include iron, copper, zinc, tin, and aluminum. , Magnesium, titanium, nickel, chromium, manganese, molybdenum, and alloys containing at least one selected from these. Among them, from the viewpoint of industrial utilization, iron and iron-containing alloys are preferable, and iron is more preferable.

The method of using the agent of the present invention as a bio-corrosion inhibitor for metal is not particularly limited, but as one aspect thereof, for example, when the metal is exposed to an environment where microorganisms that cause bio-corrosion exist, A method of allowing the agent of the present invention to exist in the environment beforehand. As a specific example of this aspect, when the fossil fuels (such as petroleum, natural gas, shale oil, shale gas, etc.) are excavated by hydraulic crushing method, liquids that can be injected into rock disks and the like under high pressure can be used. (High-pressure water) The agent of the present invention is added in advance to dissolve it, thereby suppressing the biological corrosion generated by the metal (for example, the metal pipe of the high-pressure water flow path) in contact with the high-pressure water. In another aspect, coating on the surface of a metal considered to be necessary for the inhibition of biological corrosion, or coating or dissolving or dispersing the agent of the present invention in water or an organic solvent may be mentioned. Spray method and so on.

The use form of the agent of the present invention is preferably in the form of an aqueous or oily solution in which the total concentration of the aforementioned active ingredients is within a specific range.

The total concentration of active ingredients in this solution is usually 10,000 ppm or less. From the viewpoint of cost and effect, it is preferably 0.01 ppm to 3000 ppm, and more preferably 0.1 ppm to 1000 ppm. If the concentration is less than 0.01 ppm, the bactericidal effect tends to be small, and if it exceeds 10,000 ppm, it tends to be excessive and difficult to use in terms of price. In this specification, "ppm" means "mass ppm" as long as it is not particularly limited.

The method for producing the solution is not particularly limited, and a known method or a method based on it can be used. For example, it can be manufactured by adding the aforementioned active ingredient to an appropriate liquid carrier and stirring to dissolve or disperse it. The liquid carrier includes, for example, the liquid carrier exemplified above and the like as one of the components that can be contained in the agent of the present invention.

The solution can be used by mixing it with high-pressure water used in the hydraulic crushing method, for example. When a solution is used in combination with the high-pressure water, the solution may contain components (such as a proppant, a viscosity modifier, a surfactant, an acid, etc.) that are commonly used in high-pressure water.

In addition, the solution may be applied or sprayed on the surface of a metal which is considered necessary for the inhibition of biological corrosion.

When the agent of the present invention is used, as long as the purpose of the present invention is not impaired, a known sterilization method or a method based on it can be used in combination.

For example, a known antibacterial agent may be used in combination, or a sterilization method by pH control (for example, refer to International Publication No. 2010/056114, International Publication No. 2008/134778, etc.), or a sterilization method by ultrasonic irradiation ( For example, refer to International Publication No. 2000/024679, etc.). Examples of well-known fungicides that can be used in combination with the agent of the present invention include other fungicides and the like exemplified above as one of the ingredients that can be contained in the agent of the present invention.

    [Example]    

Examples will be given below to explain the present invention in more detail, but the present invention is not limited to the following examples. The SAL and acrolein used in the examples and comparative examples are described below.

SAL: Produced from isopentenol according to the method described in Japanese Patent Application Laid-Open No. 60-224652 (purity: 98.1%)

Acrolein: manufactured by Tokyo Chemical Industry Co., Ltd., containing hydroquinone as a stabilizer

<Example 1> Sterilization test

LB medium (1 mass / vol% bacterial peptone, 0.5 mass / vol% yeast extract, 1 mass / vol% NaCl, pH 7.01) was used to culture coliform bacteria at 37 ° C for 24 hours, and then LB medium was used. diluted to 10 ⁵ cells / mL. SAL was added to it to prepare a sample with the concentration shown in Table 1. In each concentration of samples, culture was started at room temperature (about 25 ° C), and coliforms collected after 0, 10, 20, 30, and 40 minutes were transplanted into LB culture plates and cultured at 37 ° C for 24 hours. Count the number of coliform colonies after culture. The results are shown in Table 1.

As a result of using a buffer solution containing 500 ppm or more of SAL, it was found that SAL is bactericidal to microorganisms.

<Test Example 1> Thermal stability test

SAL and acrolein were added to a 50-mL three-necked flask, and the temperature was increased to 50 ° C in a nitrogen atmosphere. The content of SAL and acrolein immediately after the temperature rise was taken as 100%. The internal standard was used. Observe by calibration line method from gas chromatography. The results are shown in Table 2.

[Gas Chromatography Analysis]

Analysis equipment: GC-14A (manufactured by Shimadzu Corporation)

Detector: FID (Hydrogen Flame Ionization Detector)

Use column: DB-1701 (length: 50m, film thickness 1μm, inner diameter 0.32mm) (manufactured by Agilent Technologies)

Analysis conditions: injection temperature of 250 ° C, measurement temperature of 250 ° C

Heating conditions: 70 ℃ → (heating at 5 ℃ / min) → 250 ℃

Internal standard substance: Diglyme (diethylene glycol dimethyl ether)

After 10 hours, 99.9% remained with respect to SAL, and acrolein lost 3.4% with or without hydroquinone as a stabilizer. From this result, it is understood that the thermal stability of the SAL system is extremely higher than that of acrolein.

<Test Example 2> pH stability test

SAL and acrolein were each dissolved in a 0.5 mol / L phosphate buffer solution having a different pH to prepare a 0.1% by mass solution. 50mL of this solution was added to a sample bottle under a nitrogen gas environment, and stored at 23 ± 2 ° C. The content of SAL and acrolein at the time of preparation was taken as 100%, and the content was changed by high-speed liquid chromatography. Obtain the absolute correction line to observe. The results are shown in FIGS. 1 and 2.

From this result, it turns out that compared with acrolein, SAL-type pH stability is extremely high.

[Preparation of phosphate buffer]

pH1.7: Dissolve 4.9g of 75% phosphoric acid and 7.8g of sodium dihydrogen phosphate · 2 hydrate in 200mL of distilled water.

pH6.2: Dissolve 7.8g of sodium dihydrogen phosphate · 2 hydrate and 7.1g of disodium hydrogen phosphate in 200mL of distilled water.

pH8.1: Dissolve 0.3 g of sodium dihydrogen phosphate ‧ hydrate and 13.9 g of disodium hydrogen phosphate in 200 mL of distilled water.

[High-speed liquid chromatography analysis]

Analysis equipment: Prominence system (manufactured by Shimadzu Corporation)

Use column: Cadenza CD-C18 (length: 150m, inner diameter 4.6mm)

Developing solution: H ₂ O / MeOH = 45 / 55vol ratio, H ₃ PO ₄ = 1mol / L

Flow rate: 1mL / min

<Reference example>

SAL and acrolein are existing compounds, and their safety information has been revealed. Table 3 shows the safety-related information for reference. Compared with acrolein, SAL is known to have extremely low toxicity and is safe.

Claims (7)

A bactericide containing an α, β-unsaturated aldehyde represented by the following general formula (1) as an active ingredient, (R ¹ to R ³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an aryl group having 6 to 12 carbon atoms; however, R ¹ may be different from R ² or R ^{3 is} connected to each other to form an alkylene group having 2 to 6 carbon atoms, and R ¹ and R ^{2 are} not hydrogen atoms at the same time). The fungicide according to claim 1, wherein R ¹ to R ³ are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms. The fungicide according to claim 1 or 2, wherein R ³ is a hydrogen atom.     The fungicide according to any one of claims 1 to 3, which is used for inhibiting biological corrosion of metals.         A sterilization method using a bactericide according to any one of claims 1 to 4.         A method for inhibiting biological corrosion of a metal by using a bactericide according to any one of claims 1 to 4.         The use of a bactericide according to any one of claims 1 to 4 is for inhibiting biological corrosion of metals.