Prats Elena, Galindo Juan C, Bazzalo Maria E, León Alberto, Macías Francisco A, Rubiales Diego, Jorrín Jesús V
Grupo de Investigación Bioquímica Vegetal y Agrícola, Departamento de Bioquímica y Biología Molecular (ETSIAM), Universidad de Córdoba, Apdo. 3048, 14080 Cordoba, Spain.
J Chem Ecol. 2007 Dec;33(12):2245-53. doi: 10.1007/s10886-007-9388-9. Epub 2007 Nov 22.
In a previous study, we observed that bract and corolla extracts from a Sclerotinia sclerotiorum-resistant sunflower contained high amounts of the known coumarins scopoletin, scopolin, and ayapin. There was a correlation between coumarin concentration and disease resistance. Thin layer chromatography showed higher concentrations of three other compounds in the resistant genotype when compared to the susceptible. A bioassay-directed purification that used column chromatography and HPLC allowed the isolation of a new compound, 3-acetyl-4-acetoxyacetophenone, and known compounds, demethoxyencecalin and 3-acetyl-4-hydroxyacetophenone. Structures were assigned from spectral data, and bioactivities were characterized by in vitro bioassays against S. sclerotiorum. The new compound, 3-acetyl-4-acetoxyacetophenone, had an antifungal activity similar to the coumarin ayapin, previously described as a potent Sclerotinia inhibitor. The speed and simplicity by which these compounds can be detected make them suitable for use in screening procedures that may identify genotypes with valuable levels of resistance. A screening of seven sunflower genotypes in a field experiment showed a correlation between these compounds and resistance to Sclerotinia.
在之前的一项研究中，我们观察到，一种抗核盘菌向日葵的苞片和花冠提取物含有大量已知的香豆素——东莨菪素、东莨菪苷和阿亚品。香豆素浓度与抗病性之间存在相关性。薄层色谱分析表明，与感病基因型相比，抗病基因型中其他三种化合物的浓度更高。采用柱色谱和高效液相色谱进行的生物测定导向纯化，使得一种新化合物3-乙酰基-4-乙酰氧基苯乙酮以及已知化合物去甲氧基恩卡灵和3-乙酰基-4-羟基苯乙酮得以分离。通过光谱数据确定了结构，并通过针对核盘菌的体外生物测定对生物活性进行了表征。新化合物3-乙酰基-4-乙酰氧基苯乙酮具有与香豆素阿亚品相似的抗真菌活性，阿亚品此前被描述为一种有效的核盘菌抑制剂。这些化合物能够被检测的速度和简便性，使其适用于可能识别具有有价值抗性水平基因型的筛选程序。在一项田间试验中对七种向日葵基因型进行的筛选表明，这些化合物与对核盘菌的抗性之间存在相关性。
