著者

宮門 正和

出版者

日本農薬学会

雑誌

日本農薬学会誌 (ISSN:03851559)

巻号頁・発行日

vol.11, no.3, pp.483-492, 1986-08-20

被引用文献数

3

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For several years, our research group at Sumitomo has been conducting an extensive search for new biologically active natural products. Some of the isolated natural products could be looked upon as prototype models for synthetic research to develop new agrochemicals. In this paper, the followings are described as examples of our research : (i) The extract of black pepper fruits (Piper nigrum L.) exhibited strong insecticidal activity against several pests. A new amide, N-isobutyl-11-(3, 4-methylenedioxyphenyl)-2E, 4E, 10E-2, 4, 10-undeca-trienamide (pipercide), as well as two structurally related amides, were isolated as insecticidal principles. From the results of synthetic studies, N-isobutyl-12-(3-trifluoromethylphenoxy)-2E, 4E-2, 4-dodecadienamide was found to have especially potent activity. This amide, as well as the amides from pepper plants, exhibited notable paralyzing effects and lethal activity against pyrethroid-resistant houseflies. Electro-physiological studies using the central nerve cord of the American cockroach demonstrated that these amides are neurotoxic compounds. (ii) The chloroform extract of the stems and leaves of May apple (Podophyllum peltatum L.) showed fungicidal activity against rice blast. Three new 2-pyrones (podoblastin A, B and C) were isolated as fungicidal components and their structures were determined by synthesis. Fungicidal activities against rice blast were greatly improved by structural modifications, and 3-(2-oxodecanyl)-4-hydroxy-6-n-propyl-5, 6-dihydropyran-2-one was selected as the most potent compound. The preventive effect of this compound against rice blast was most successful, however the curative and systemic effects require further improvement. (iii) A biphenyl(3, 5-dimethoxy-4-hydroxybiphenyl, aucuparin), as well as a new dibenzofuran (2, 4-dimethoxy-3-hydroxydibenzofuran, eriobofuran), were isolated as phytoalexins from fungi-infected loquat trees (Eriobotrya japonica L.). The structure of eriobofuran was determined by synthesis. Eriobofuran exhibited fungicidal activity against Pestalotia funerea (phytopathogenic fungi to loquat), however it did not show any activity against several fungi which are non-pathogenic to loquat. The biological significance of the self-induction of the phytoalexins in the loquat tree was considered in relation to plant resistance against fungal attack.

著者

小林 裕子 俣野 修身 後藤 真康

出版者

日本農薬学会

雑誌

日本農薬学会誌 (ISSN:03851559)

巻号頁・発行日

vol.11, no.1, pp.81-84, 1986-02-20

被引用文献数

4

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Ethylenebisdithiocarbamates (EBDCs)を施用後の農作物中に残留するethylenethiourea (ETU)の分析法を確立する目的で, たまねぎ, トマト, すいかおよびレタス中のETUの残留分析法について検討した.たまねぎ, トマト, すいかおよびレタス中のETUを含水メタノールで抽出し, 溶媒を留去する.濃縮液を水酸化アンモニウム溶液あるいは水酸化ナトリウム溶液でpH8に調整し, Extrelut^[○!R]カラムで精製したのち, 紫外部吸収検出器付高速液体クロマトグラフィーで定量した.検出限界は, 0.01ppmであり, 回収率は, 76∿90%であった.この方法はExtrelut^[○!R]カラムに供する試料をフッ化カリウム等で前処理するNitzの方法より簡潔性, 迅速性等の点で優れている.

著者

小野田 恭久 今村 昌子

出版者

日本農薬学会

雑誌

日本農薬学会誌 (ISSN:03851559)

巻号頁・発行日

vol.5, no.1, pp.101-105, 1980-02-20

被引用文献数

2

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茶浸出液中の残留農薬分析操作に, 塩基性酢酸鉛による除タンニン操作を加え, 各農薬の抽出法を検討し, 以下のような結果を得た.1) 茶浸出液と抽出溶媒間のエマルジョンの生成が抑制され, 分離が良好となり, 脱水操作も短時間に行なうことができ, 告示法にくらべ高回収率を得ることができた.また, このとき大部分の色素類も同時に除去され, ガスクロマトグラム上の夾雑ピークの数も減少するなど, 茶浸出液中の残留農薬分析において, 塩基性酢酸鉛による除タンニン操作はきわめて有効な手段であった.2) メソミルの抽出溶媒は酢酸エチルがよく, 告示法の操作を省略できた.3) 告示法では, DMTP, イソキサチオン, PAP, ホサロン, TPNで抽出精製法がすべて異なっているが, 本試験の結果, 同一溶媒による同時抽出が可能となり, 操作の省略や抽出溶媒の種類を少なくすることができるなど, 分析試料の調整法が簡便となった.