47 植物防御系においてペルオキシダーゼが関与する化学的防御機構の解析(口頭発表の部)

• 小林 昭雄

  岡山大農

• 小口 泰

  岡山大農

• 神崎 浩

  岡山大農

• 梶山 慎一郎

  岡山大農

• 河津 一儀

  岡山大農

書誌事項

タイトル別名

• 47 THE ROLE OF PEROXIDASE IN THE CHEMICAL DEFENCE OF PLANTS : A NOVEL PEROXIDASE INHIBITOR AND A NEW TYPE OF BIOACTIVE PHENOLICS PRODUCED BY PEROXIDASE

抄録

Plants induce varied resistance-response toward microbial challenge. In order to establish an infection, pathogenic fungi must break such defense barriers as lignin, phytoalexins, and hydrolytic enzymes. At the early stage of infection, POD (peroxidase) activity is enhanced dramatically. POD and lignin accumulates at the infected site and then protects from further fungal invasion. The suppression of lignin deposition at the site might be of advantage to susceptible pathogenic fungi. We, therefore, conducted a comprehensive screening to obtain POD inhibitors from fungal cultures and a potent radical scavenger named ST-1 was isolated from a fungus, and its chemical structure was elucidated to be 1,3-dihydro-4,5,6-trihydroxy-1,3-dimethoxy-7-methylisobenzofuran by a combination of chemical modification and spectroscopic techniques. ST-1 effectively scavenged oxygen radicals and also suppressed the phytoalexin accumulation in kidney bean. These results suggested that such a mechanism can be enumerated as one of significant defense systems intervening plants and microbes. On the other hand, the POD, activated upon pathogenic challenge, could convert common plant phenolics into bioactive compounds which interfered with pathogen and insect attacks. This idea prompted us to examine the possibility. Guaiacol and other phenols were chosen as model substrates for the enzyme reaction system, and several products with novel structures were confirmed to have unique biological activities. This paper deals with the chemical structures of a novel radical scavenger (ST-1) and the POD products with anti-microbial activities and phytotoxicities.

収録刊行物

• 天然有機化合物討論会講演要旨集

  天然有機化合物討論会講演要旨集 35 (0), 361-368, 1993

  天然有機化合物討論会実行委員会

詳細情報

• CRID: 1390282681054282496
• NII論文ID: 110006679211
• DOI: 10.24496/tennenyuki.35.0_361
• ISSN: 24331856
• 本文言語コード: ja
• データソース種別:
  • JaLC
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可