JPH09194317A - Agent for controlling house dust mite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce an agent for controlling house dust mite with excellent mite controlling effect by clathrating an extract of Haedokuso (phryma leptostachya ssp. asiatica) to form a specific clathrate and using the clathrate as an active component. SOLUTION: A compound produced by clathrating a Haedokuso extract with a cyclodextrin is used as the objective agent. The Haedokuso extract can be produced e.g. by extracting the whole plant of Haedokuso, preferably raw or dried root with an organic solvent and concentrating the product. The clathration of the extract with cyclodextrin is carried out by adding Haedokuso extract to a saturated aqueous solution of cyclodextrin, stirring the mixture and collecting the precipitate. The controlling agent for house dust mite is effective for the control of mites such as Dermatophagoides farinae, Tyrophagus dimidiatus, Glycyphagus privatus Oudemans, Cheyletus malaccensis Oudemans, etc., and is used e.g. by scattering to Tatami mat (rush mat), carpet, mattress, sofa, quilt, closet, warehouse, etc.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an agent for controlling indoor dust mites.

[0002]

2. Description of the Related Art It is known from JP-A-62-20727 that extracts of Haedsou, especially certain sesquilignan derivatives contained in the extracts have insecticidal activity against houseflies.
No. 8 publication.

[0003]

However, even if the Haedsouw extract is used as it is for controlling indoor dust mites, the effect is poor, and in practice, the Haedsouw extract is unsuitable for use as an indoor dust mites control agent. It was enough.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides an excellent indoor dust mite control agent, wherein the indoor dust mite control agent is effective for a Haedsow extract which is included in cyclodextrin. It is contained as an ingredient.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The Haedsou extract used in the present invention can be obtained, for example, by extracting the whole plant of Haedsou, preferably the fresh grass or dried product of roots with an organic solvent and concentrating it.

Examples of the organic solvent used include lower alcohols such as methanol and ethanol, ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate and butyl acetate, ethers such as ethyl ether and isopropyl ether, toluene and xylene. And the like, halogenated hydrocarbons such as chloroform, methylene chloride, and percene, and mixtures thereof. The organic solvent is usually used in an amount of 1 to 20 times the fresh weight of Haedsou, and the immersion extraction, shake extraction,
The Haedsou extract can be obtained according to a general method for extracting plant components such as continuous extraction using a Soxhlet extractor.

The obtained Haedsou extract is, for example,
Concentrate to less than 1/10 the volume of extraction, and if necessary, 0.5-
After washing with about 2% by weight of a mineral acid such as hydrochloric acid, about 2-10% by weight of sodium hydrogen carbonate solution, about 0.5-2% by weight of sodium hydroxide aqueous solution, the organic solvent is distilled off to obtain a Haedsou extract. be able to.

Furthermore, according to the description of JP-A-62-207278, it is also possible to obtain a fraction containing a large amount of the sesquilignan derivative described in the publication by a chromatographic method and use it as a Haedsou extract. it can.

The cyclodextrin used in the present invention is a saccharide having a structure in which 6 to 12 glucose molecules, usually 6 to 8 glucose molecules are cyclically bonded, and a derivative thereof, which is a synthetic saccharide produced from starch. And its derivatives, naturally occurring saccharide derivatives and the like. The synthetic product is obtained, for example, as follows. Cyclodextrin glucanotransferase (CGT-ase) is allowed to act on starch or a starch hydrolyzate to cleave and decompose the helical structure in the starch molecule, and the cleaved ends are joined to obtain cyclodextrin. Further, maltosyl cyclodextrin can be obtained by further adding maltose to the obtained cyclodextrin through an α-1,6-bond by utilizing the reverse synthesis reaction of the debranching enzyme pullulanase.

Specific examples of the cyclodextrin used in the present invention include natural derivatives such as glucosyl cyclodextrin, maltotriosyl cyclodextrin and panosyl cyclodextrin, dimethyl cyclodextrin, trimethyl cyclodextrin and hydroxypropyl cyclodextrin. Examples include synthetic derivatives such as dextrin.

For encapsulating the Haedsou extract in cyclodextrin, a method usually used for obtaining a cyclodextrin inclusion body such as a saturated aqueous solution method, a kneading method or a drying method is used.

According to the saturated aqueous solution method, for example, the Haedsou extract is added to a saturated aqueous solution of cyclodextrin, and the mixture is stirred and mixed for 30 minutes to several hours, whereby the Haedsou extract included in the cyclodextrin is precipitated. can get. If necessary, it is possible to obtain a powdery target product by evaporating or cooling the water, taking out the precipitate, and then drying it.

According to the kneading method, for example, a small amount of water (usually 0.3 to 3 times the weight of cyclodextrin) is added to cyclodextrin to form a paste, and the Haedsou extract is added to this and kneaded well. If necessary, this may be dried and then washed with ether or the like to give a powder clathrate.

According to the drying method, for example, Haedsou extract is added to a concentrated aqueous solution of cyclodextrin, stirred to form an inclusion body, and then spray-dried or freeze-dried to obtain a powder inclusion body.

The agent for controlling indoor dust mite of the present invention may be the cyclodextrin clathrate itself obtained as described above, but it is usually in the form of being held on a suitable carrier, for example, a solid carrier. . The indoor dust mite control agent of the present invention may further contain other acaricide, insecticide, fungicide, synergist and the like.

When the cyclodextrin clathrate is to be held on a solid carrier, it is mixed with a solid carrier such as kaolin clay, bentonite, talc, diatomaceous earth, etc., and if necessary, an auxiliary agent for formulation such as a surfactant is added, followed by a conventional method. To form a powder or granules. As the surfactant used at this time, alkyl sulfate ester salt, alkyl sulfonate,
Examples thereof include anionic surfactants such as alkylaryl sulfonates and nonionic surfactants such as polyoxyethylene alkyl ethers and polyoxyethylene sorbitan fatty acid esters.

The indoor dust mite control agent of the present invention is, for example,
Dermatophagoides farinae, Dermatophagoides farinae and other mites, Plutella xylostella mites, Mite mites and other mites, dust mites such as dust mite, house dust mite, scabbard mites, pest mites such as stag beetle mite, phytoseiid mite, indoor dust mites and house dust mites Used in tatami mats, carpets, mattresses,
It is used on sofas, futons, closets, warehouses, etc. by methods such as spraying. The throughput is generally in the level of JP-A-62-207.
The amount of the crude extract obtained according to Example 1 of Japanese Patent No. 278 is about 100 mg to ²⁰ g per 1 m ^{2 of the} area to be controlled.

[0018]

Next, the present invention will be described in more detail with reference to Examples. A crude extract obtained according to Example 1 of JP-A-62-207278 was used as a Haedsou extract in the following examples. Example 1 To 85 ml of a 1.7% aqueous solution of β-cyclodextrin, 5 g of an acetone solution containing 500 mg of the Haedsou extract was added.
After stirring at room temperature for 4 hours, the precipitate formed by cooling to 0 ° C. was collected by filtration, dried, washed twice with ethyl ether, dried again, and then crushed in a mortar and pulverized in a mortar to extract cyclodextrin inclusion bodies. (Haedsou extract content 25%) was obtained. Talc was added to this and mixed well to obtain a dust containing 2% by weight of Haedsow extract. The obtained powder is
A piece of 5 cm × 5 cm carpet (loop type made of polyester) was uniformly treated so that the amount of Haedsou extract was 2 g / m ² to obtain a mite-proof carpet for testing.

For comparison in the test example (Example 2) described later
A production example of the anti-mite carpet used is shown as Reference Example 1.
You. Reference Example 1 2 ml of an acetone solution containing 5 mg of Haedsou extract was added to 5
cm × 5cm piece of carpet (polyester loop
Type), the amount of Haedsou extract is 2g / m ^TwoBecomes
Impregnated and air dried with acetone
-It was a pet.

Example 2 180 mg of a medium containing about 2000 heads / g of Dermatophagoides farinae,
Each of the anti-mite carpet and the non-agent-treated carpet obtained in Example 1 and Reference Example 1 was inoculated and kept at a temperature of 25 ° C. and a relative humidity of 65%. The number of living mites was counted from 1 day to 35 days after inoculation, and the growth inhibition rate (%) was calculated by the following formula.

## EQU1 ## Growth inhibition rate (%) = (1−T / C) × 100 T: Number of live mites on acaricide-proof carpet C: Number of live mites on a drug-untreated carpet Table 1 shows the results.

[0021]

[Table 1]

[0022]

INDUSTRIAL APPLICABILITY The indoor dust mite control agent of the present invention has an excellent mite control effect.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Keisuke Watanabe 4-2-1 Takashi Takarazuka-shi, Hyogo Sumitomo Kagaku Kogyo Co., Ltd.

Claims (1)

[Claims] 1. An indoor dust mite control agent, which comprises, as an active ingredient, a Haedsou extract which is included in cyclodextrin.