title: Eudesmanolides from Wedelia trilobata (L.) Hitchc. as potential inducers of plant systemic acquired resistance.
abstract: 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.
authors.affiliation: State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences , Kunming 650201, Yunnan, China.
authors.forename: Yating
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaojiang
authors.initials: X
authors.lastname: Hao
authors.forename: Shifei
authors.initials: S
authors.lastname: Li
authors.forename: Hongping
authors.initials: H
authors.lastname: He
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Yan
authors.forename: Yongdui
authors.initials: Y
authors.lastname: Chen
authors.forename: Jiahong
authors.initials: J
authors.lastname: Dong
authors.forename: Zhongkai
authors.initials: Z
authors.lastname: Zhang
authors.forename: Shunlin
authors.initials: S
authors.lastname: Li
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology; D060467:Disease Resistance / Q000187:drug effects*; D015394:Molecular Structure; D010935:Plant Diseases / Q000517:prevention & control / Q000821:virology*; D018515:Plant Leaves / Q000187:drug effects / Q000821:virology; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D014026:Nicotiana / Q000187:drug effects / Q000821:virology*; D014027:Tobacco Mosaic Virus / Q000187:drug effects; D031209:Wedelia / Q000737:chemistry*
chemical_list: D000998:Antiviral Agents; D012717:Sesquiterpenes; C476916:eudesmanolide