JP2754605B2 - Red tide plankton control agent - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an agent for controlling red tide plankton for reducing or eliminating damage caused by red tide plankton.

[Conventional technology]

In recent years, diversification of the occurrence of red tides due to eutrophication in bays and coastal areas, and the occurrence of hypoxia have resulted in reduced feeding, poor growth or death of cultured fish, which has had a great impact on the fisheries industry. I have.

To solve this, it is necessary to control red tide plankton, which is the cause, but the controlling agent used for this purpose is a powerful control agent that causes red tide plankton to promptly cause protoplasmic discharge and kill it It is strongly desired that the compound has a low cost of use, has no adverse effect on marine organisms other than red tide plankton, and is a biodegradable compound.

As a conventionally known red tide plankton control agent,
There are surfactants such as polyoxyethylene laurylamine and polyoxyethylene sorbitan monolaurate,
Also, "Natural Marine Products Chemistry" edited by Isao Kitagawa, Chemistry Special Volume 111, Volume 6
Page 9 (Chemical Doujinshi, 1987) states that 6,9,12,15-octadecatetraenoic acid, arachidonic acid, eicosapentaenoic acid,
It is disclosed that highly unsaturated fatty acids such as γ-linolenic acid and linoleic acid and derivatives thereof are effective for controlling red tide plankton.

[Problems to be solved by the invention]

However, none of the above known controlling agents can satisfy all of the above-mentioned required properties, and in particular, the above-mentioned surfactants are inferior in controlling properties, which are the characteristics of, and in order to achieve the intended purpose. Must be used in very large quantities, which has the adverse effect on marine organisms other than red tide plankton, which is a characteristic of this case, when fish toxicity becomes stronger.

In addition, among the above-mentioned polyunsaturated fatty acids and derivatives thereof, there are those having relatively good controllability of red tide plankton, but it still takes a long time to exhibit effective control, that is, it is inferior in fast-acting effect In most cases, considering the diffusion loss due to the tide, etc., it is difficult to achieve the intended purpose unless the amount used is also large, so that the same adverse effects as in the case of the surfactant cannot be avoided. It has not yet been put to practical use.

The present invention has been made in view of the above situation,
It is an object of the present invention to provide an extremely practical control agent that can satisfy the above-mentioned requirements, in particular, has excellent immediate effect on the control of red tide plankton, and can reduce or eliminate the damage caused by the plankton with a smaller amount of use. .

[Means for solving the problem]

The present inventors have conducted intensive studies to achieve the above object, and as a result, using a specific antibiotic consisting of a compound containing a hydrocarbon chain in which a plurality of double bonds are conjugated in a molecule, the red tide plankton Knowing that very good results could be obtained for control, the present invention was completed.

That is, the present invention, as an antifungal agent or an anti-yeast agent containing a hydrocarbon chain having a conjugated double bond in the molecule,
The present invention relates to a red tide plankton control agent comprising at least one selected from etruscomycin, pimaricin, perimycin, and filipin as an active ingredient.

[Structure and operation of the invention]

Antifungal agent or anti-yeast agent used in the present invention,
As described above, the number of carbon atoms having a conjugated double bond is usually 5 to 5.
An antibiotic consisting of a compound containing 20 hydrocarbon chains in the molecule, which acts on microorganisms and cell membranes to change their properties (permeability and speed of substances such as ions) and kill microorganisms. Things. Specifically, etruscomycin [Biochim, Biophs. Acta, 339 , 57 (1974)],
Pimaricin [Adv. Lipid Res., 14 , 127 (1976)], Perimycin [Biochim. Biophy. Acta, 374 , 159 (1974)],
Filipin [Biochim, Biophs. Acta, 339 , 57 (1974)],
Is mentioned.

In the present invention, such an antifungal agent or an anti-yeast agent is remarkably excellent in controlling red tide plankton as compared with the known agent for controlling red tide plankton, and also satisfies the above-mentioned required characteristics (1) to (4). In particular, it has been found that the use of a small amount of the compound exhibits remarkably excellent control properties, thereby avoiding adverse effects on marine organisms other than red tide plankton such as fish toxicity.

The reason why such excellent controllability is exhibited is not necessarily clear at present, but the above-mentioned antifungal agent or anti-yeast agent alters the cell membrane of red tide plankton, and increases the intracellular ions. It is considered that the resulting increase in osmotic pressure causes the protoplasm to be moistened, resulting in protoplasm discharge and prompt death.

In the present invention, in order to apply a controlling agent containing the above-mentioned antifungal agent or anti-yeast agent as an active ingredient to the sea surface where red tide plankton is generated, for example, the controlling agent may be sprayed alone or in the form of an aqueous solution. Good and lipophilic substances may be sprayed in combination with an appropriate surfactant, or may be sprayed after dissolving in a lower alcohol such as ethanol.

Application rate, in consideration of the adsorption loss to the diffusion and debris by the wave, often to the 10~2,000kg about per sea 1km ^2, and the like are taken into consideration impact on the environment pollution and farmed fish
It is particularly preferable to make it as small as about 10 to 500 kg. If the purpose is only to inhibit red tide plankton growth, the application may be less than 10 kg.

〔The invention's effect〕

As described above, by using the compound of the present invention,
Significant damage by red tide plankton in general fishing grounds and aquaculture fishing grounds can be reduced or eliminated, and stable and high-profitable fishing grounds can be realized.

〔Example〕

Next, examples of the present invention will be described in more detail.

Using Examples 1 Coster Co. 12Wells, this composition below; distilled water _{1,000ml NaCl 24.5g MgSO 4 · 7H 2} O 4.9g MgCl 2 · 6H 2 O 4.1g KCl 0.75g CaCl 2 1.11g pH = 7.9 After injection of 2 ml of a physiological experiment medium consisting of ~ 8.0, the following composition was further added thereto: seawater 100 ml NaCO ₃ 12 mg Na ₂ HPO ₄・ 12H ₂ O 0.5 mg EDTA-Fe 26 μg EDTA-Mn 33 μg VB ₁₂ 0.1 μg Thiamine・ Red tide plankton (Heteroshig) in a culture medium consisting of HCl 10μg Biotine 0.1μg
those were cultured ma akasiwo), it was seeded such that the number of red tide plankton is about 10 ⁴ / well.

Next, an aqueous solution containing a red tide plankton control agent of the present invention and a surfactant (sorbitan monooleate) shown in Table 1 was added to this medium, and a physiological experiment test was conducted at 25 ° C. The amount of red tide plankton control agent used was 0.5 ppm in the final concentration in the culture medium, and that of the surfactant was 0.01 ppm.
ppm.

By such a physiological experiment test, the change of red tide plankton was observed with a microscope every predetermined time after the addition of the controlling agent. The results are shown in Table 1 below together with the results obtained when only a surfactant was added as a blank test. In addition,
The control agents used in the present invention are etruscomycin, pimaricin, perimycin and phillipin, and their chemical structural formulas are as follows.

Comparative Example 1 A physiological experiment test was conducted in the same manner as in Example 1 except that the control agent for red tide plankton shown in Table 1 below was used, and the results are also shown in Table 1. In the control agent used here, each fatty acid composition of fish oil, fish oil fatty acid, fish oil fatty acid ethyl and fish oil fatty acid sodium salt, myristic acid, palmitic acid and stearic acid: 35% by weight,
Eicosapentaenoic acid: 15% by weight, docosahexaenoic acid:
8% by weight, other unsaturated fatty acids: 42% by weight.

As is clear from Table 1, the control agent of Comparative Example 1 using a polyunsaturated fatty acid or a derivative thereof is inferior to the control agent of red tide plankton, whereas the antifungal agent or the anti-yeast agent of Example 1 is used. It can be seen that the control agent using the compound can exhibit very good controllability with excellent fast-acting properties.

Example 2 The concentration of pimaricin, a red tide plankton control agent used in Example 1, was adjusted to 5 ppm, 1 ppm, 0.5 ppm, 0.1 ppm,
Except for changing to 0.05ppm, 0.01ppm and 0.005ppm,
A physiological experiment test was performed in the same manner as in Example 1. The results were as shown in Table 2 below.

From Table 2 above, it is clear that the greater the amount of pimaricin used, the more effective it is. However, it is clear that even a small use of about 0.05 ppm is effective in quickly controlling red tide plankton.

Claims (1)

(57) [Claims] 1. An antifungal or anti-yeast agent containing a hydrocarbon chain having a conjugated double bond in the molecule, at least one selected from etruscomycin, pimaricin, perimycin, and filipin as an active ingredient. Red tide plankton control agent.