Tellier Frederique, Fritz Rene, Kerhoas Lucien, Ducrot Paul-Henri, Einhorn Jacques, Carlin-Sinclair Abel, Leroux Pierre
UMR 1290, INRA, route de Saint-Cyr, F-78026 Versailles, France.
J Agric Food Chem. 2008 Sep 10;56(17):8050-7. doi: 10.1021/jf8010917. Epub 2008 Aug 12.
The metabolism of cymoxanil [1-(2-cyano-2-methoxyiminoacetyl)-3-ethyl urea] by a very sensitive strain of Botrytis cinerea toward this fungicide was studied by using [2-(14)C]-cymoxanil. Labeled cymoxanil was added either in a culture of this strain or in its enzymatic extract. The main metabolites, detected in biological samples, were isolated and identified by mass and NMR spectrometry. Their identification allowed us to show that this strain quickly metabolized cymoxanil according to at least three enzymatic pathways: (i) cyclization leading, after hydrolysis, to ethyl parabanic acid, (ii) reduction giving demethoxylated cymoxanil, and (iii) hydrolysis and reduction followed by acetylation leading to N-acetylcyanoglycine. In a cell-free extract of the same strain, only the first and the second enzymatic reactions, quoted above, occurred. Biological tests showed that, among all the metabolites, only N-acetylcyanoglycine is fungitoxic toward this sensitive strain.
利用[2-(14)C]-霜脲氰，研究了对该杀菌剂高度敏感的灰葡萄孢菌株对霜脲氰[1-(2-氰基-2-甲氧基亚氨基乙酰基)-3-乙基脲]的代谢情况。将标记的霜脲氰添加到该菌株的培养物或其酶提取物中。在生物样品中检测到的主要代谢产物通过质谱和核磁共振光谱进行分离和鉴定。对它们的鉴定使我们能够表明，该菌株至少通过三种酶促途径快速代谢霜脲氰：(i)环化反应，水解后生成对羟基苯甲酸乙酯，(ii)还原反应生成去甲氧基霜脲氰，(iii)水解和还原反应后乙酰化生成N-乙酰基氰基甘氨酸。在同一菌株的无细胞提取物中，仅发生上述的第一种和第二种酶促反应。生物测试表明，在所有代谢产物中，只有N-乙酰基氰基甘氨酸对该敏感菌株具有杀真菌毒性。
