at almost all the concentrations examined. These results sugrin skeleton decrease the plant growth inhibitory activity. This
⑴ Tseng, C.F., Iwakami, S., Mikajiri, A., Shibuya, M.,
Hanaoka, F., Ebizuka, Y., Padmawinata, K. and Sankawa,
presumption was supported by additional examination with
U.: Inhibition of in vitro prostaglandin and leukotriene
6,7-dihydroxycoumarin（esculetin）and 7-methoxycoumarin.
The efficacy of 6,7-dihydroxycoumarin on respective hypo-
biosyntheses by cinnamoyl-β-phenethylamine and N-
gested that the existence of substituent group at C-6 in couma-
cotyl and root growth of sesame seedlings was 101±7.6%
and 81 ± 7.2% at 0.1 mM, and 68 ± 3.4% and 39 ± 2.7% at
0.3 mM by comparing with the control, which was lower than
that of umbelliferone and similar to that of scopoletin. On the
other hand, the efficacy of 7-methoxycoumarin on respective
hypocotyl and root growth of sesame seedlings was 37±2.2%
acyldopamine derivatives. Chem. Pharm. Bull., 40,
396–400（1992）.
⑵ Malalavidhane, T.S., Wickramasinghe, S.M.D.N. and
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Thulin, M., Warfa, A.M., Hassan, A.O., Elmi, A.H., Ab-
and 39±4.2% at 0.1 mM, and 3.4±0.9% and 9.4±1.4% at
0.3 mM by comparing with the control, which was higher than
Inventory of plants used in traditional medicine in Soma-
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Two coumarin derivatives isolated in this study have been
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Exudation of umbelliferone and scopoletin from root of
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are released from living roots of water spinach, the plants
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HPLC or TLC analysis, in which peaks or spots corresponding
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extracts. The 1H NMR spectra of the isolated compounds were
38
香川大学農学部学術報告 第72巻，2020
エンツァイ（Ipomoea aquatica）の根および根滲出物に含まれる植物生長阻害物質
近江由里・深井智穂・古本敏夫
要 約
エンツァイの根から２種類の植物生長阻害物質を単離し，これらの物質がクマリン類であるウンベリフェロン（7-ヒ
ドロキシ-2H-1-ベンゾピラン-2-オン）とスコポレチン（7-ヒドロキシ-6-メトキシ-2H-1-ベンゾピラン-2-オン）であ
ることを明らかにした．ゴマとレタスを用いた生物検定において，ウンベリフェロンはスコポレチンよりも強い生長阻
害活性を示した．これらの植物生長阻害物質がエンツァイの根から放出されていることを，エンツァイ水耕液から得た
根滲出物を分析することにより実証した．
...
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