JP2003292401A - Exterminator against red tide plankton - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an exterminator against red tide planktons, having excellent dispersibility to seawater, exterminating effect on red tide planktons and storage stability and low toxicity to fish and is not subject to regulation of application to the sea. <P>SOLUTION: The exterminator for red tide planktons comprises 1-99 wt.% of one or more kinds of fatty acids represented by general formula (1): R<SP>1</SP>COOH [R<SP>1</SP>is a 7-23C alkyl group] and 99-1 wt.% of one or more kinds of fatty acid dispersants. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a practical red tide plankton repellent.

[0002]

2. Description of the Related Art Up to now, highly unsaturated fatty acids (marine natural product chemistry, N
o111, p69-70 (1987), Kagaku Dojin, polyunsaturated fatty acid, an oil containing the fatty acid immobilized on a fibrous material (JP-A-6-1701), a higher fatty acid or a salt thereof (JP-A-63). -10704), polyethylene glycol ester of polyunsaturated fatty acid (Japanese Patent Application Laid-Open No. 1-4770).
1), ethylene oxide adduct of aliphatic alcohol (JP-A-50-100228, JP-A-50-12382)
1), ethylene oxide adduct of fatty acid amide (JP-A-50-117923), ethylene oxide adduct of alkylamine (JP-A-50-123822), alkylene oxide adduct of aliphatic alcohol, alkylene oxide adduct of fatty acid, fatty acid A method using an alkylene oxide adduct of amide, an alkylene oxide adduct of alkylamine (JP-A-6-16504) and the like is known.

However, most of these substances are not listed in Appendix 1 of "Act for Enforcement of Law Concerning Prevention of Marine Pollution and Marine Disasters", Appendix I, and in practice, approval by government agencies is required when spraying to the ocean. Become. In addition, highly unsaturated fatty acids and polyunsaturated fatty acids lack oxidative stability (AJSt
Riton et al., Oil & Soap, 22 , 81 (1945), RT Holman et al., J. Am.
Oil Chem. Soc., 24 , 127 (1947)), but is not satisfactory in terms of storage stability.

Some saturated fatty acids are permitted to be sprayed to the ocean as described in Appendix 1 of "Act for Enforcement of Law Concerning Prevention of Marine Pollution and Marine Disasters", but solubility in seawater However, a red tide plankton pesticide that is small and has no practical use has been obtained.

[0005]

In order to be a practical red tide plankton pesticide, it is desired to meet the following requirements. (1) Effective in low concentration spraying, (2) Little adverse effect on fish, shellfish, algae, etc. (3) Degraded sprayed drug in a short time, (4) Drug Cheap and easily available, and (5) Not subject to regulations such as discharge from ships.

Of these, the item (5) is an important point for practical use in the control of red tide plankton in seawater.

The present invention provides a red tide plankton repellent which has excellent dispersibility in seawater and an effect of controlling red tide plankton, is excellent in storage stability, has low fish toxicity, and does not regulate the application to the ocean. The purpose is to do.

[0008]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that by incorporating a specific fatty acid and a dispersant, the fatty acid is easily dispersed in seawater, Efficacy of red tide plankton, which is effective for the plankton such as Heterocapsa circularis kama, Shatonella, Gymnodinium, etc., which are known as red tide plankton generated in the region, and has low fish toxicity, and can achieve the intended purpose The present invention has been completed, and the present invention has been completed based on such findings.

That is, the red tide plankton pesticide of the present invention is represented by the general formula (1) R ¹ COOH (1) [wherein R ¹ represents an alkyl group having 7 to 23 carbon atoms]. ]
1 to 99% by weight of one or more of the fatty acids represented by and 99 to 1 or 2 or more of the fatty acid dispersant
It is characterized by containing 1% by weight.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The fatty acid represented by the general formula (1) relating to the red tide plankton pesticide of the present invention (hereinafter abbreviated as "present fatty acid") is a saturated fatty acid having 8 to 24 carbon atoms. Specific examples thereof include octanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, eicosanoic acid, docosanoic acid, and tetraconic acid. Fatty acids with 7 or less carbon atoms are highly toxic to fish and may adversely affect seafood when sprayed.
The above fatty acids are not preferable because they have poor water solubility and have a small effect of controlling red tide plankton.

Among these fatty acids, they are excellent in the effect of controlling red tide plankton, and they are described in "Enforcement Ordinance for the Prevention of Marine Pollution and Maritime Disasters", Appendix 1-2. In terms of being a substance that is not a target of ( ¹⁾ , a fatty acid in which R ¹ is an alkyl group having 13 to 17 carbon atoms is preferable, and tetradecanoic acid, hexadecanoic acid, and octadecanoic acid are particularly recommended.

The red tide plankton repellent of the present invention contains 1 to 99 parts by weight of the present fatty acid and 99 to 1% by weight of a fatty acid dispersant (hereinafter referred to as "present dispersant"). The dispersant is represented by the general formula (2) [In the formula, R ² represents an alkyl group or an alkenyl group having 11 to 19 carbon atoms. EO represents an oxyethylene group. l,
m and n each represent an integer of 1 to 30, and l + m +
n is 4-30. ] Mono-fatty acid represented by polyoxyethylene sorbitan, glycerin, ethyl alcohol, dipropylene glycol, sorbitol solution, triacetyl glycerin, tripropylene glycol, propyl alcohol, propylene glycol, butyl alcohol, hexylene glycol, polyglycerin and general formula _{(3) HO (CH 2 CH} 2 O) kH (3) [ wherein, k is a number ranging from 2 to 20. ] The polyethylene glycol represented by these is mentioned.

Among these dispersants, the general formula (2) which itself has an effect of controlling red tide plankton [In the formula, R ² represents an alkyl group or an alkenyl group having 11 to 19 carbon atoms. EO represents an oxyethylene group. l,
m and n each represent an integer of 1 to 30, and l + m +
n is 4-30. ] Mono-fatty acid polyoxyethylene sorbitan represented by the following is preferable.

R ² in the general formula (2) has 11 carbon atoms.
To 19 alkyl or alkenyl groups. Specific examples of the fatty acid which is a constituent component of the monofatty acid polyoxyethylene sorbitan of the general formula (2) include dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, octadecenoic acid, coconut oil fatty acid and palm oil fatty acid. It is illustrated. Number of moles of ethylene oxide added 1, m
n represents an integer of 1 to 30, respectively, and the total number of added moles l +
m + n is 4 to 30.

Specific examples of the monofatty acid polyoxyethylene sorbitan represented by the general formula (2) include the following. -Polyoxyethylene (6) sorbitan monododecanoate (R ² = alkyl group having 11 carbon atoms, l + m + n = 6) -Polyoxyethylene (20) sorbitan monotetradecanoate (R ² = alkyl group having 13 carbon atoms, l + m + n =
20) ・ Polyoxyethylene (20) sorbitan monohexadecanoate (R ² = alkyl group having 15 carbon atoms, l + m + n =
20) ・ Polyoxyethylene (6) sorbitan monooctadecanoate (R ² = alkyl group having 17 carbon atoms, l + m + n =
6) ・ Polyoxyethylene (20) sorbitan monooctadecanoate (R ² = alkyl group having 17 carbon atoms, l + m + n =
20) Polyoxyethylene (6) sorbitan monooctadecenoate (R ² = alkenyl group having 17 carbon atoms, l + m + n =
6) Polyoxyethylene (20) sorbitan monooctadecenoate (R ² = alkenyl group having 17 carbon atoms, l + m + n
= 20)

[0016] Among them, the "Enforcement Ordinance for the Law Concerning Prevention of Marine Pollution and Maritime Disasters", Appendix 1, is
Polyoxyethylene (20) sorbitan monooleate is particularly preferred because it is a substance that is not subject to regulations such as discharge from ships.

Among the above-mentioned present fatty acid and monofatty acid polyoxyethylene sorbitan, R ¹ in the general formula (1) is
There the present fatty acids with an alkyl group having 13 to 17 carbon atoms, R ² in the general formula (2) is an alkenyl group having 17 carbon atoms, a combination of mono fatty acid polyoxyethylene sorbitan l + m + n is 20, red tide It is preferable in terms of the plankton exterminating effect and a compound that is not regulated at the time of spraying in the ocean, and among them, a combination with the present fatty acid in which R ¹ in the general formula (1) is an alkyl group having 13 to 15 carbon atoms is particularly preferable. preferable.

The mixing ratio of the present fatty acid to the monofatty acid polyoxyethylene sorbitan represented by the general formula (2) is 1 to 99% by weight, preferably 10 to 80% by weight, of at least one of the present fatty acids. At least one kind of fatty acid polyoxyethylene sorbitan is contained in an amount of 99 to 1% by weight, preferably 90 to 20% by weight. The amount of the present fatty acid is preferably less than 80% by weight because it is easily dispersed in the monofatty acid polyoxyethylene sorbitan.

When the present fatty acid is used in combination with the monofatty acid polyoxyethylene sorbitan represented by the general formula (2), it is preferable to heat and dissolve the present fatty acid to prepare a mixture of the monofatty acid polyoxyethylene sorbitan. At this time,
The mono-fatty acid polyoxyethylene sorbitan to which the present fatty acid is added may be dissolved by heating, or the mono-fatty acid polyoxyethylene sorbitan may be added to and mixed with the present fatty acid. Also, the added party may be reversed.

In the dispersant, the general formula (3) HO (CH ₂ CH ₂ O) kH (3) [wherein k represents a number in the range of 2 to 20]. ] Polyethylene glycol represented by the following is also preferable. K in the general formula (3) represents the number of moles of ethylene oxide polymerized, but it is not necessarily an integer because it is usually represented by the average degree of polymerization. If k is less than 2, it is subject to regulations such as discharge from ships because it is not listed in Appendix 1-2 of the Law Enforcement Ordinance on Prevention of Marine Pollution and Marine Disasters, and when k is greater than 20 However, the liquidity is lost, which is not preferable. Among these, those having k of 3 to 15 are preferable because the dispersibility of the present fatty acid is particularly good.

The mixing ratio of the present fatty acid to the polyethylene glycol represented by the general formula (3) is preferably 10 to 80% by weight, more preferably 30 to 70% by weight, of at least one of the present fatty acids and polyethylene glycol. 90 to 20% by weight, and more preferably 70 to
It is preferable to contain 30% by weight. When the content of the present fatty acid is more than 10% by weight, the concentration of the active ingredient becomes high, so that the amount of the pesticide used is small, which is more practical. From the viewpoint of good dispersibility in polyethylene glycol, it is preferable that the present fatty acid is less than 80% by weight.

When the present fatty acid is mixed with the polyethylene glycol represented by the general formula (3), it is preferable to heat and dissolve the present fatty acid to prepare a mixture with polyethylene glycol. At this time, polyethylene glycol to which fatty acid is added may be dissolved by heating, or pre-melted fatty acid may be added and mixed into polyethylene glycol. The added party may be reversed.

The red tide plankton repellent of the present invention can be used by adsorbing it to one or more adsorbents selected from sodium aluminosilicate, kaolin, magnesium hydroxide, calcium carbonate and clay. By adsorbing to the adsorbent, it can be made into a powdery pesticide composition, which makes it easy to handle, and after spraying, the adsorbent does not immediately diffuse near the sea surface, but the pesticide gradually precipitates while settling. It is possible to spread the effect to red tide at a deeper position.

The amount of the red tide plankton pesticide adsorbed on the adsorbent is 1 with respect to the total amount of the adsorbent and the red tide plankton pesticide.
It is 0 to 80% by weight, preferably 10 to 60% by weight. If it is less than 10% by weight, the concentration of the active ingredient becomes small and a large amount of the pesticide composition must be used, which is inferior in practical use. On the other hand, if it is more than 80% by weight, it is not preferable because powdering becomes difficult.

In the red tide plankton pesticide composition of the present invention, the adsorbent is agitated, and the red tide plankton pesticide is liquefied as it is or after heating, if necessary, to liquefy. It can be manufactured by adding. In addition, the red tide plankton pesticide may be manufactured as it is, or if necessary, heated and liquefied and then stirred, and the adsorbent is gradually added thereto to manufacture.

The red tide plankton repellent and the red tide plankton repellent composition of the present invention may be applied to the red tide plankton generation area as they are, or may be applied to water or seawater after being applied. As a spraying method, dipper,
Examples include spraying by a sprayer and the like, aerial spraying by a helicopter, and the like. Further, by preliminarily placing a material such as wood impregnated with a red tide plankton pesticide or a cloth-like material placed in the red tide plankton generation area, it is possible to prevent a large amount of red tide plankton from being generated.

[0027]

EXAMPLES The present invention will be described in detail below with reference to examples. The properties of each mixture were evaluated by the following methods.

Cell destruction test 90 ml of red tide plankton repellent prepared by heat-sterilized seawater to a predetermined concentration in a 200 ml glass container having a foamed silicone stopper that allows air to pass in and out of which germs cannot pass.
l and 10 ml of plankton culture solution, add 3 at 20 ℃
After standing for 0 minutes, count the number of cells that stopped motility and the number of cells that were destroyed by elution of cell fluid on a slide glass with a cell counting scale. The minimum concentration of the red tide plankton pesticide when it reached was defined as the minimum concentration of cell destruction (ppm). The plankton used in the test was Heterocapsa circularis kama, and the EMS medium (pH = 8.
0) using 20 to 25 ° C. and 3000 to 6000 Lux
Subculture was carried out under the condition of (14 L / 10 to 15 D), and a culture medium containing plankton of about 1000 cells / ml was used.

Composition of EMS medium 1000 ml of filtered seawater NaNO3 120mg K2HPO4 5mg 50 ml of soil extract Vitamin B1 100 μg Vitamin B12 1 μg Biotin 1 μg EDTA-Fe 259 μg EDTA-Mn 332 μg Tris (hydroxymethyl) aminomethane 1g

Storage stability The red tide plankton pesticide composition obtained by adsorbing the red tide plankton pesticide on a predetermined adsorbent was allowed to stand at 40 ° C. for 3 months, and the presence or absence of caking was observed. Those without caking were marked with "○", and those with caking recognized were marked with "x".

Example 1 70% by weight of tetradecanoic acid was dissolved by heating and mixed with 30% by weight of polyoxyethylene (20) sorbitan monooleate to obtain a red tide plankton repellent (1). Table 1 shows the measurement results of the minimum concentration of cell destruction of the obtained pesticide.

Examples 2-9 Example 1 except that the fatty acids and compositions listed in Table 1 were used.
The red tide plankton pesticides (2) to (9) were prepared in the same manner as in. Table 1 shows the measurement results of the minimum concentration of cell destruction of the obtained pesticide.

[0033]

Example 10 50% by weight of tetradecanoic acid was dissolved by heating to give a molecular weight of 15
0 (k = 3.0) polyethylene glycol 50% by weight
To obtain a red tide plankton pesticide (10). Table 3 shows the measurement results of the minimum concentration of cell destruction of the obtained pesticide.

Examples 11 to 18 Red tide plankton pesticides (11) to (18) were prepared in the same manner as in Example 10 except that the fatty acids, polyethylene glycols and compositions shown in Table 2 were used. Table 2 shows the measurement results of the minimum concentration of cell destruction of the obtained pesticide.

[0036]

Example 19 Red tide plankton pesticide (1) 20 prepared in Example 1
% By weight was added to 80% by weight of sodium aluminosilicate under stirring to obtain a red tide plankton repellent composition (1). Table 2 shows the evaluation results of the storage stability of the obtained pesticide composition.

Examples 20 to 28 Red tide plankton repellent compositions (2) to (9) were prepared in the same manner as in Example 19 except that the red tide plankton repellent, adsorbent and composition shown in Table 3 were used. Prepared. Table 3 shows the evaluation results of the storage stability of the obtained pesticide composition.

[0039]

Example 29 Red tide plankton repellent prepared in Example 10 (10)
20% by weight of sodium aluminosilicate 80 with stirring
In addition to wt%, red tide plankton pesticide composition (10)
Got Table 4 shows the evaluation results of the storage stability of the obtained pesticide composition.

Examples 30 to 38 Red tide plankton repellent compositions (11) to (19) were prepared in the same manner as in Example 29 except that the red tide plankton repellent, adsorbent and composition shown in Table 4 were used. Prepared. Table 4 shows the evaluation results of the storage stability of the obtained pesticide composition.

[0042]

Comparative Example 1 The minimum cell disruption concentration was measured using only octadecanoic acid. At this time, octadecanoic acid was not uniformly mixed with the plankton culture solution, but was in a state of floating on the surface of the culture solution.
In addition, 20% by weight of octadecanoic acid was mixed with 80% by weight of sodium aluminosilicate under stirring, and the obtained composition was evaluated for storage stability. These results are the fifth
Shown in the table.

Comparative Example 2 A fatty acid was prepared in the same manner as in Example 10 except that polyethylene glycol having 5,8,11,14-eicosatetraenoic acid at 50% by weight and a molecular weight of 200 (k = 4.1) was used. A mixture of polyethylene glycol was prepared. The minimum cell disruption concentration of this mixture is shown in Table 5. Also, 20% by weight of this mixture was mixed with 80% sodium aluminosilicate under stirring.
The resulting composition was mixed in a weight percentage and the storage stability was evaluated. The results obtained are shown in Table 5.

[0045]

[0046]

INDUSTRIAL APPLICABILITY According to the present invention, by combining a saturated fatty acid, which has not been practically used so far, with a dispersant, the red tide plankton exterminating property is excellent, and the unsaturated fatty acid which has been conventionally known can be obtained. In comparison, it is possible to obtain a highly practical red tide plankton pesticide that is excellent in storage stability and does not become a legal regulation when applied to the ocean.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhisa Mitsuya             13 Yakura-cho, Yashimajima, Fushimi-ku, Kyoto-shi, Kyoto New             Within Nippon Rika Co., Ltd. (72) Inventor Mikio Nakanishi             161 at 2492 Hakonoura, Hannan City, Osaka Prefecture F-term (reference) 4H011 AD01 BA01 BB06 BC08 BC20                       DA02 DA14 DD01 DF04

Claims (8)

[Claims] 1. General formula (1) R ¹ COOH (1) [wherein, R ¹ represents an alkyl group having 7 to 23 carbon atoms. ]
1 to 99% by weight of one or more of the fatty acids represented by and 99 to 1 or 2 or more of the fatty acid dispersant
A red tide plankton repellent containing 1% by weight. 2. R ¹ in the general formula (1) has 1 carbon atom.
The red tide plankton repellent according to claim 1, which has an alkyl group of 3 to 17. 3. The red tide plankton repellent according to claim 1, wherein the fatty acid represented by the general formula (1) is tetradecanoic acid, hexadecanoic acid or octadecanoic acid. 4. The fatty acid dispersant has the general formula (2): [In the formula, R ² represents an alkyl group or an alkenyl group having 11 to 19 carbon atoms. EO represents an oxyethylene group. l,
m and n each represent an integer of 1 to 30, and l + m +
n is 4-30. ] Mono-fatty acid represented by polyoxyethylene sorbitan, glycerin, ethyl alcohol, dipropylene glycol, sorbitol solution, triacetyl glycerin, tripropylene glycol, propyl alcohol, propylene glycol, butyl alcohol, hexylene glycol, polyglycerin and general formula _{(3) HO (CH 2 CH} 2 O) kH (3) [ wherein, k is a number ranging from 2 to 20. ] The red tide plankton repellent of Claim 1 which is 1 type (s) or 2 or more types selected from the group which consists of polyethylene glycol represented by these. 5. The red tide plankton repellent according to claim 4, wherein the fatty acid dispersant is a monofatty acid polyoxyethylene sorbitan represented by the general formula (2). 6. R ¹ in the general formula (1) has 13 carbon atoms.
To 17 alkyl groups, R ² in the general formula (2)
Is an alkenyl group having 17 carbon atoms and l + m + n is 20
The red tide plankton repellent according to claim 5. 7. The fatty acid represented by the general formula (1) is used in an amount of 10 to 80% by weight, and the polyethylene glycol represented by the general formula (3) is used in an amount of 90 to 90%.
The red tide plankton repellent according to claim 4, which contains 20% by weight. 8. 10 to 80% by weight of the red tide plankton repellent according to claim 1 or 2 selected from sodium aluminosilicate, kaolin, magnesium hydroxide, calcium carbonate and clay. Adsorbent 9 above
A red tide plankton repellent composition which is adsorbed to 0 to 20% by weight.