JP2004196677A - Sterilizer for marine adhesive bacterium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a sterilizer which is used for marine adhesive bacteria, is inexpensive, and little affects environments. <P>SOLUTION: This sterilizer used for the marine adhesive bacteria contains at least one selected from the group consisting of organism extracts, spices, polysaccharides, organic acids and proteins as an active ingredient. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a bactericide for marine attached bacteria, and more particularly, to a bactericide used for antifouling purposes in ship bottom paints and the like.
[0002]
[Prior art]
It is known that marine periphyton often adheres to the bottom of ships and the surface of underwater structures in groups or as a community. In particular, fouling of the ship bottom caused by large attached organisms such as barnacles increases frictional resistance against seawater, causing a decrease in ship speed and excessive consumption of fuel. It is also known that such fouling causes a decrease in buoyancy, local and crevice corrosion, etc., and antifouling measures are indispensable measures from the viewpoint of ship operation.
[0003]
2. Description of the Related Art Conventionally, as a measure for preventing fouling, a paint containing an antifouling agent has been applied to the bottom of a ship. As this antifouling agent, an organotin having a growth inhibitory effect on barnacles was used, and the effect of preventing adhesion was excellent.
[0004]
However, organotin compounds are hardly decomposable, and their effects on the human body and the environment with respect to their growth inhibitory toxicity have become a problem. In 1989, they were designated as one of the specified chemical substances under the Chemical Substances Control Law, and their production and import were banned. And its use has recently been limited. Copper nitrite is used as a substitute, but copper is also subject to long-term regulation as an environmental hormone, and the elution concentration must be at least four times higher than that of organotin. Therefore, accumulation in the environment and ecosystem is a concern.
[0005]
Instead of such an adhesion inhibitor having a high load on the environment and ecosystem, a method of suppressing adhesion with a low environmental load has been proposed. This method suppresses the adhesion of barnacle larvae promoted by the biofilm by removing the colonies of the adherent bacteria (biofilm) generated in the initial stage of the biofouling by lytic enzymes, and consequently, the large adherence. This is a method to prevent the attachment of living things. However, it is economically difficult to mass-cultivate the lytic enzyme required for ship bottom paint, and there has been a demand for an inexpensive and adhering bacteria-removing agent with a low environmental load.
[0006]
[Problems to be solved by the invention]
The present invention has been made in view of the above-mentioned problems of the related art, and an object of the present invention is to provide a bactericide for marine attached bacteria that is inexpensive and has little effect on the environment by using a natural organic compound.
[0007]
[Means for Solving the Problems]
The present inventors have conducted intensive studies on the chemical resistance of marine adherent bacteria that form biofilms, and found that natural organic compounds used as preservatives, spices, and shelf life improvers are marine resistant bacteria. The present inventors have found that they show a bactericidal effect, and have accomplished the present invention based on this finding.
[0008]
That is, the present invention relates to a bactericide for marine adherent bacteria, comprising as an active ingredient at least one selected from the group consisting of plant extracts, spices, polysaccharides, organic acids, and proteins.
[0009]
The bactericide for marine attached bacteria of the present invention is suitably used for ship bottom paints.
[0010]
When the fungicide of the present invention is applied to the bottom of a ship and the components are eluted, a biofilm derived from marine attached bacteria is killed and the attachment of marine organisms is suppressed. It is intended to provide an agent for removing adherent bacteria, characterized by using a natural organic compound having a small particle size.
[0011]
Furthermore, the present invention relates to an agent for preventing marine organisms from adhering to the bottom of a ship, which contains at least one selected from the group consisting of biological extracts, spices, polysaccharides, organic acids and proteins as active ingredients.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention is a natural organic compound having a killing effect on marine attached bacteria, and examples of the natural organic compound used include plant extracts, spices, polysaccharides, organic acids, and proteins.
[0013]
Biological extracts include plant extracts and animal extracts. As the plant extract, for example, tannin, hiba oil, hinoki oil, cinnamic acid, gallic acid, forsythia extract, Kumazasa extract, Moso bamboo extract, mustard, wasabi oil, egonoki extract, honoki extract and the like are used. As an animal extract, chitosan, protamine and the like are used. In addition, the main components and artificial synthetic products thereof are also used, for example, hinokitiol and tropolone organic compounds, which are the main components of hiba oil and hinoki oil, or 2,6- which is the main component of Kumazasa extract and Moso bamboo extract. For example, dimethoxy-1,4-benzoquinone or a quinone derivative, or an allyl isothiocyanate compound which is a main component of mustard or wasabi oil may be used.
[0014]
As spices, for example, cinnamon, caraway, oregano, thyme, clove, lemon, nutmeg, laurel, saffron, coriander, sansho, marjoram, vanilla and the like are used. In addition, the main components and artificial synthetic products are also used, and the components of the above-mentioned spices are cinamic aldehyde, cinamic alcohol, carvone, carvacrol, thymol, eugenol, limo-nene, β-pinene, cineole, safrole, Linanol, citronellol, terpineol, vanillin and the like are used.
[0015]
As the polysaccharide, for example, agar oligosaccharides, pectin degradation products, chitosan and its degradation products are used. Since chitosan and its decomposed product exhibit bactericidal properties at pH 6 or more, it is desirable to use the mixture with an inorganic compound such as clay or zeolite having acidity.
[0016]
As organic acids, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, isovaleric acid, pivalic acid, lauric acid, myristic acid, palmitic acid, stearic acid, monocarboxylic acids such as oleic acid, oxalic acid, malonic acid, Dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, aromatic mono- or dicarboxylic acids such as benzoic acid, salicylic acid, phthalic acid, malic acid or derivatives thereof, citric acid, etc. And the like.
[0017]
Examples of proteins include lysozyme, protamine, and polylysine.
[0018]
Preferred fungicides include hinokitiol, spices, and Moso bamboo extract.
[0019]
Examples of marine adherent bacteria include adherent bacteria belonging to the genera Pseudomonas, Alteromonas, and Pseudoalteromonas.
[0020]
The disinfectant of the present invention exerts its adhesion-preventing effect by being directly applied to the ship bottom or dispersed in a paint and applied and gradually dissolved in seawater. In addition, for example, in order to suppress the dissolution rate, a method of applying a bactericide to the coating resin by chemical bonding, a method of adsorbing the bactericide on a porous inorganic carrier such as clay and silica gel, and dispersing and dispersing them in the coating material. The same anti-adhesion effect can be obtained by using. The bactericide of the present invention eluted by these methods has no toxicity to the human body or large animals, and has no accumulation effect on the environment.
[0021]
The amount of the fungicide of the present invention may be appropriately determined depending on the application target, and the active ingredient is allowed to act at an active ingredient concentration of about 0.005 to 20%, preferably about 0.01 to 5%. Is preferred.
[0022]
The bactericide of the present invention can be formulated and used in known dosage forms such as liquids (including water suspensions and oils), pastes, powders, and granules, depending on the purpose of use. it can. Preferably, for example, a liquid agent is used. In order to formulate a liquid formulation, the compound represented by the formula (1) may be appropriately dissolved or dispersed in a solvent. The solvent used at this time is not particularly limited as long as it can dissolve or disperse the compound represented by the general formula (1).
[0023]
Specific examples of these solvents include, for example, water, for example, alcoholic solvents such as methanol, ethanol, n-propanol, iso-propanol, n-butanol, and tert-butanol, for example, ethylene glycol, diethylene glycol, polyethylene glycol, Propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,4-butanediol, 1,5-pentanediol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol mono Glycol solvents such as ethyl ether and tripropylene glycol monomethyl ether, for example, Ketone solvents such as ton, methyl ethyl ketone, and methyl isobutyl ketone; for example, ether solvents such as dioxane, tetrahydrofuran, and ethyl ether; for example, ester solvents such as ethyl acetate, butyl acetate, and isobutyl acetate; for example, benzene, toluene, and xylene And aromatic solvents such as methylnaphthalene and solvent naphtha, for example, halogenated hydrocarbon solvents such as carbon tetrachloride, chloroform and methylene chloride, and polar solvents such as dimethylformamide, dimethylsulfoxide and acetonitrile. These solvents may be used alone or in combination of two or more.
[0024]
When the fungicide of the present invention is used by being incorporated into a ship bottom paint or other film forming agent applied to the bottom of a ship, for example, as a solid or as a liquid, the active ingredient is removed from the coating film by seawater. And the effect can be favorably maintained.
[0025]
【The invention's effect】
Advantageous Effects of Invention According to the present invention, it is possible to provide a bioadhesion inhibitor that is inexpensive and has a small impact on the environment while exhibiting a bioadhesion prevention effect.
[0026]
【Example】
Next, the present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.
Example 1
Marine adherent bacteria (Pseudoalteromonas carrageenovora) were inoculated into 5 ml of a liquid medium (MB liquid medium) and cultured at 28 ° C. with shaking until the logarithmic growth phase. Thereafter, the liquid medium was removed by centrifugation. 5 ml of seawater was added to the cultured bacteria after centrifugation, and the cells were washed twice by centrifugation and suspension of the seawater solution, and then 10 ml of seawater was added. The resulting solution was diluted to an initial concentration of 3 to 5 × 10 ⁶ cells / ml, stirred well, and cultured at 28 ° C. with shaking until the beginning of logarithmic growth.
[0027]
Hinokitiol (10 mg) was placed in a plastic tube, diluted with 5 ml of seawater, and stirred. Left for 2 hours with occasional shaking. Thereafter, the mixture was centrifuged, and 0.5 ml of the supernatant was mixed with the bacterial cell fluid cultured with shaking until the beginning of logarithmic growth, and the growth curve was measured.
[0028]
The shaking speed during the measurement of the growth curve was 70 rpm, the measurement interval was 5 minutes, and the total exercise time was 15 hours.
[0029]
FIG. 1 shows the time-dependent changes in the optical density of the cell culture with hinokiol added and the culture with no hinokiol added. The optical density of the culture without added hinokitiol increased over time. This means that the bacteria grew in the culture and the optical density increased. On the other hand, it was found that the density of the culture solution to which hinokitiol was added did not increase, and that the growth of bacteria could be suppressed.
Example 2
5 mL of seawater was added to each of 10 mg of cinnamon alcohol, vanillin, cinnamaldehyde, ethyl isocyanate, and benzoquinone to prepare a solution. After that, 0.5 ml of the solution was mixed with the cell fluid cultured until the beginning of logarithmic growth, and the growth curve was measured. As an example, the results for cinnamon alcohol are shown in FIG.
[0030]
Hinokitiol, cinnamon alcohol, vanillin, cinnamaldehyde, ethyl isocyanate, and benzoquinone, which were confirmed to have the effects of the bactericide for marine attached bacteria in Examples 1 and 2, were blended into the hull bottom paint, applied to the test object, and applied to the actual sea area. Preliminary experiments conducted in this way confirm that there is a remarkable effect on the prevention of fouling caused by large attached organisms such as barnacles, as compared with the case where a ship bottom paint not containing these compounds is applied.
[Brief description of the drawings]
FIG. 1 shows the time-dependent changes in the optical density of a cell culture medium containing hinokiol and a culture medium (blank) not containing hinokiol.
FIG. 2 shows the time-dependent changes in the optical density of a cell culture medium containing cinnamon alcohol and a culture medium (blank) without addition.

Claims (4)

A fungicide for marine attached bacteria comprising at least one selected from the group consisting of biological extracts, spices, polysaccharides, organic acids and proteins as active ingredients. The fungicide for marine attached bacteria according to claim 1, which is used for ship bottom paint. At least one selected from the group consisting of a biological extract, a spice, a polysaccharide, an organic acid, and a protein is adsorbed to a carrier as necessary, and blended into a ship bottom paint, and applied to the ship bottom. To prevent marine organisms from adhering. An agent for preventing marine organisms from adhering to the bottom of a ship, comprising as an active ingredient at least one selected from the group consisting of biological extracts, spices, polysaccharides, organic acids, and proteins.

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