JPS6128641B2 - - Google Patents

Description

[Detailed description of the invention]

Dehydroacetic acid, sorbic acid, or any of their salts are useful as low-toxicity antibacterial and fungicidal agents. However, when used as an antibacterial and antifungal agent for industrial products such as paints, pastes, and adhesives, its effectiveness is not necessarily sufficient, and its range of use is limited.
However, attempts have been made to widen the antibacterial spectrum by combining various antibacterial and antifungal agents in order to improve their antibacterial and antifungal abilities. It can only be obtained by
The reality is that it is difficult to recognize a dramatic improvement in efficacy. However, the present inventors have developed a composition comprising (A) at least one of dehydroacetic acid or an alkali metal salt thereof, or sorbic acid or an alkali metal salt thereof, and (B) 2-pyridinethiol-1-oxide or a salt thereof. discovered that the antibacterial and antifungal effects were synergistically improved, and completed the present invention. Both (A) and (B) of the present invention are known as antibacterial and antifungal agents, but it would be impossible to predict based on conventional knowledge that the effects described above would be obtained when these are used together. There is no such thing. Component (A) of the present invention is at least one of dehydroacetic acid, sorbic acid, or an alkali metal salt thereof. Examples of the salt include sodium dehydroacetate, potassium dehydroacetate, sodium sorbate, potassium sorbate, and the like. On the other hand, component (B) has the general formula

It is 2-pyridinethiol-1-oxide represented by the formula: In the present invention, sodium salt

[Formula] Zinc salt

[Formula] etc. are also preferably used. There is no particular limit to the mixing ratio of component (A) and component (B), but the mixing ratio of component (B) to (A) should be 0.5 to 40% by weight.
When used within such a range, the synergistic effect is particularly significant, so it is desirable to use the compound within this range. The amount of the composition of the present invention to be used varies depending on the type of object, so it cannot be unconditionally prescribed, but it is usually 50~
If added at around 4000ppm, the antibacterial and antifungal effect will be fully demonstrated. In addition, the composition of the present invention may contain other antibacterial agents, antifungal agents, surfactants, fragrances, polyamide carboxylic acids such as EDTA, oxycarboxylic acids such as citric acid, condensed phosphates, etc., as necessary. It is also possible to add an auxiliary agent, such as a chelating agent, as appropriate. The composition of the present invention can be added to any industrial product requiring antibacterial and antifungal properties. Examples include various paints, pastes, petroleum products, plastic molded products, textiles, leather, wood products, processed paper products, cosmetics, pharmaceuticals, medical equipment, and parts for industrial facilities and buildings. Various objects can be mentioned. Furthermore, it can also be used for agricultural products such as grains, fruits, and vegetables. Next, the composition of the present invention will be explained in more detail by giving examples. Example 1 Both components (A) and (B) were added to a potato dextrose agar medium at the concentrations shown in the table, and a filamentous fungal spore suspension as shown in the table was added dropwise, and the mixture was kept at a constant temperature of 28°C. The cells were cultured in a vessel for two weeks, and the presence or absence of growth was measured. However, + indicates growth. ±; Some growth -; No growth

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[Table] Example 2 Tryptone 0.5%, yeast extract 0.5%, glucose
Add both ingredients (A) and (B) to a medium containing 0.1% dipotassium phosphate, 0.1% dipotassium phosphate, and 2% agar at the concentrations shown in the table below, inoculate with various bacteria, and incubate at 37℃. The cells were cultured for 4 days and the presence or absence of growth was examined. However, + indicates growth. ±; Slightly growing −; Not growing

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[Table] Test Example 1 A 10% aqueous solution glue of polyvinyl alcohol was prepared. This is divided into 3 sections, 1 section contains no additives,
To the second section, 1000 ppm of sodium dehydroacetate was added, and to the third section, 250 ppm of sodium dehydroacetate and 10 ppm of 2-pyridinethiol-1-oxide sodium salt were added. Then Epicoccum in each ward
SP, Sephalosporium SP, Fusarium
A spore suspension of a filamentous fungus consisting of oxysporium is used as a glue.
After inoculating 0.3ml per 100g, it was placed in a thermostat at 30°C for 14 days. Mold broke out in Ward 1 within two days.
In the second ward, mold broke out in five days. There was no mold at all in Ward 3. Test Example 2 The same experiment as Test Example 1 was conducted except that sodium sorbate was used instead of sodium dehydroacetate. As a result, ward 1 developed mold in 3 days, ward 2 developed mold in 5 days, and ward 3 had no mold at all. Test Example 3 Mosquito coil powder 5g with no drug added (1
Ward), added with 500ppm of sodium dehydroacetate (Section 2), sodium dehydroacetate
250ppm and 2-pyridinethiol-1-oxide sodium salt 10ppm added (3rd section),
The above three types of mixtures were prepared, each mixed thoroughly with 8 ml of water, and molded into a disk shape with a radius of 5 cm and a thickness of 0.5 cm. Aspergillus for each sample
niger, Penicillium luteum, Cladosporium
herbaum, Pullularia pullulans, Fusarium
0.3 ml of a suspension of filamentous fungal spores consisting of M. oxyporium (a loopful of each strain was mixed in 5 ml of sterilized water) was added. This product was cultured for two weeks in a thermostatic chamber at 28°C and 90% humidity, and the growth of mold was examined. The 1st ward developed mold after 2 days, the 2nd ward developed mold after 5 days, and the 3rd ward developed mold after 5 days.
There was no mold in the ward. Test Example 4 Add 2% agar to polyvinyl acetate emulsion (solid content 10%). Next, there is the one with no drug added (1st section), the one with 1000 ppm of sodium dehydroacetate added (2nd section), the one with 250 ppm of sodium dehydroacetate and 10 ppm of 2-pyridinethiol-1-oxide sodium salt (3rd section). Three samples were prepared. Aspergillus niger spore suspension was added dropwise to this, and the mixture was cultured in a 28°C incubator. In the 1st ward, mold developed in 2 days, in the 2nd ward it developed in 5 days, and in the 3rd ward no mold developed even after a week. Test Example 5 For starch paste containing 5% wheat starch, no drug added (1st section), 500ppm sodium dehydroacetate added (2nd section), 100ppm sodium dehydroacetate and 50ppm 2-pyridinethiol-1-oxide
(3 sections), and the above three types of samples were prepared. Aspergillun niger for each sample,
Penicillum citrinum, Cladosporium herbaum,
After inoculating a spore suspension consisting of Chaetomium globosum, the development of mold was observed in a thermostatic chamber at 28°C. The 1st ward developed mold in 2 days, the 2nd ward developed mold in 4 days, and the 3rd ward developed mold.
No mold developed even after 21 days. Test Example 6 Regarding fiber wall material (Type 3 Orion coated wall), no chemicals added (1st section), sodium dehydroacetate 0.1
% addition (2nd section), sodium dehydroacetate 0.09%
and 0.01% addition of 2-pyridinethiol-1-oxide sodium salt (3 sections). Three types of samples were prepared. Mix each of these thoroughly with water, apply a thin layer on a veneer board, and after 2 days of air-drying,
It was cut into cm-sized pieces and peeled off from the plywood. A drop of Aspergillus niger spore suspension was placed on the fiberboard, and the board was placed in a constant humidity chamber at 28°C and 91% humidity to examine the growth of mold. The first ward developed mold after two days, the second ward developed mold after three days, but the third ward had not developed mold for over a week. The results of Test Examples 1 to 6 are summarized in the table.

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[Table] Example 3 After sterilizing a culture solution (PH7.0) containing 1% peptone, 1% meat extract, and 0.1% salt,
ml was dispensed into L-shaped tubes. Next, a predetermined amount of an antibacterial and fungicidal agent as shown in the table was added, and 0.1 ml of a bacterial suspension as shown in the table (number of bacteria: 5 x ¹⁰⁴ cells/ml) was added, and the mixture was kept at 37°C for 48 hours. Reciprocating shaking culture was performed. The growth status of bacteria was observed by measuring the number of bacteria in 1 ml of culture solution. The results are shown in the table. In addition, the number of bacteria in the initial culture solution was 5 × ¹⁰² cells/ml.
It is.

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[Table] Example 4 After sterilizing a 5% starch aqueous solution, 100 ml thereof is added to a 250 ml sample bottle. Next, add a predetermined amount of the antibacterial and fungicidal agent shown in the table and stir thoroughly, then add 1 ml of a mold spore suspension (number of spores: 5 x 10 ⁶ /ml) as shown in the table, and stir again. and seal tightly. The mold was left at 30°C for one week and the growth of mold was observed. The growth status was expressed by measuring the number of mold spores generated per 1 g of starch aqueous solution. The results are shown in the table. In addition, 5×10 ⁴ molds are contained in 1 g of the initial starch aqueous solution.

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Claims (1)

[Claims] 1. An antibacterial and antifungal composition comprising (A) at least one of dehydroacetic acid or its alkali metal salt or sorbic acid or its alkali metal salt and (B) pyridinethiol-1-oxide or its salt.