高度不飽和脂肪酸アラキドン酸による赤潮ラフィド藻<i>Heterosigma akashiwo</i>の殺藻機構

DOI 日本農学文献記事索引 Web Site 参考文献43件

書誌事項

タイトル別名
  • Mechanisms of algicidal effects in the red-tide raphidophycean flagellate <i>Heterosigma akashiwo</i> due to the highly unsaturated fatty acid arachidonic acid
  • 高度不飽和脂肪酸アラキドン酸による赤潮ラフィド藻Heterosigma akashiwoの殺藻機構
  • コウド フホウワ シボウサン アラキドンサン ニ ヨル アカシオ ラフィド ソウ Heterosigma akashiwo ノ サツソウ キコウ

この論文をさがす

抄録

<p>Effects of scavenger enzymes for active oxygen such as superoxide dismutase (SOD) and catalase, and aquaporin-I inhibiters such as HgCl2 and tetraethylammonium (TEA) on the algicidal activity of arachidonic acid (AA) to the red-tide raphidophycean flagellate Heterosigma akashiwo, and also the effect of exposure to AA on fatty acid composition and morphology of the cells, and the incorporation of deuterium oxide (D2O) into the cells were examined in order to make clear the mechanisms which harmful/toxic flagellates were killed due to the effects of a highly unsaturated fatty acid.</p><p>Algicidal activity was not suppressed by the addition of SOD and/or catalase, but was suppressed by the additions of HgCl2 and TEA. The survival rate of H. akashiwo was increased by the addition of HgCl2 at 1×10-4–1×102 nM in the presence of a 300 ng mL-1 of AA (survival rate was 0％), and the maximum survival rate was 50–55％ at 1×10-2–3×10-1 nM. In the TEA, the algicidal activity was suppressed at 1×10-4–1×102 mM and the maximum survival rate was 60–65％ at 1×10-2–1×10-1 mM.</p><p>The morphology of H. akashiwo changed from an elliptic to a round, swelled shape with the survival rate decreasing, and the active swimming cell numbers also decreased upon exposure to AA. Furthermore incorporation of water into H.akashiwo, analyzed with D2O as a tracer, was promoted by exposure to AA. These phenomena, except the rounding of the shape, were suppressed by the addition of TEA. On the other hand, AA content in the cells significantly increased upon exposure to AA, and the increase was not affected by the addition of TEA.</p><p>These results suggest that a possible factor contributing to the algicidal activity of AA in H. akashiwo seems to be swelling that brings about the rupture of cells caused by changing the membrane structure into one that cannot withstand an increase in intracellular pressure resulting from accumulation of AA in the membrane and the acceleration of water intake by promoting the activity of aquaporin-I. Toxic effects of active oxygen derived from autoxidation of AA is not considered to be a major cause of the algicidal activity.</p>

収録刊行物

参考文献 (43)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ