State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, Yunnan, China.
J Agric Food Chem. 2013 Apr 24;61(16):3884-90. doi: 10.1021/jf400390e. Epub 2013 Apr 12.
Ten eudesmanolides (1-10) including five new ones (1-4 and 6) were isolated from the whole plant of Wedelia trilobata (L.) Hitchc., a notoriously invasive weed in South China. As main constituents of W. trilobata, eight of these eudesmanolides were tested for their antitobacco mosaic virus (TMV) activities by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the tested compounds, at 10 μg/mL, showed strong antiviral activities in the pretreated tobacco plants with inhibition rates ranging from 46.7% to 76.5%, significantly higher than that of the positive control, ningnanmycin (13.5%). Their potential of inducing systemic acquired resistance (SAR) was also evaluated, and compounds 1 and 8 showed excellent induction activities. Furthermore, it was found that different concentrations of compound 1 promoted phenylalanine ammonia-lyase (PAL) activity in tobacco plants. To our knowledge, this is the first report that eudesmanolides could induce resistance in tobacco plants against the viral pathogen TMV.
从中国南方一种著名的入侵性杂草三叶鬼针草（Wedelia trilobata（L.）Hitchc.）的全草中分离得到了 10 个桉叶烷型倍半萜（1-10），其中包括 5 个新化合物（1-4 和 6）。作为三叶鬼针草的主要成分，对其中的 8 个桉叶烷型倍半萜进行了传统半叶和叶盘法以及 Western blot 分析测试其抗烟草花叶病毒（TMV）活性。所有测试化合物在 10 μg/mL 时对预处理烟草植物均显示出较强的抗病毒活性，抑制率为 46.7%至 76.5%，明显高于阳性对照宁南霉素（13.5%）。还评估了它们诱导系统获得性抗性（SAR）的潜力，化合物 1 和 8 表现出优异的诱导活性。此外，发现化合物 1 的不同浓度可促进烟草植物中苯丙氨酸解氨酶（PAL）的活性。据我们所知，这是第一个报道桉叶烷型倍半萜可诱导烟草植物对病毒病原体 TMV 产生抗性的报告。
