title: Phenolic compounds from Merremia umbellata subsp. orientalis and their allelopathic effects on Arabidopsis seed germination.
abstract: A bioassay-directed phytochemical study was carried out to investigate potential allelochemicals of the invasive plant Merremia umbellata subsp. orientalis (Hall. f.). Eight phenolic compounds, including a salicylic acid (SA)-derived new natural product, SA 2-O-β-D-(3',6'-dicaffeoyl)-glucopyranoside (1), and seven known ones 2-8 were isolated and identified from two bioactive sub-fractions of the acetone extract of this plant. The structure of new compound 1 was established by spectral and chemical methods. The potential allelopathic effects of these compounds at 0.5 and 1.0 mM concentrations on the germination of Arabidopsis seeds were tested. Results showed that 2 remarkably inhibited seed germination at concentrations as low as 0.5 mM. Compound 3 only moderately inhibited seed germination at 0.5 mM, but displayed strong inhibitory bioactivity at 1.0 mM concentration. Compounds 4 and 5 showed only slight inhibitory bioactivity at 1.0 mM, while the other compounds showed no obvious inhibitory effects.
authors.affiliation: Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yan
authors.forename: Hai-Hong
authors.initials: HH
authors.lastname: Bi
authors.forename: Yong-Zhu
authors.initials: YZ
authors.lastname: Liu
authors.forename: Mei
authors.initials: M
authors.lastname: Zhang
authors.forename: Zhong-Yu
authors.initials: ZY
authors.lastname: Zhou
authors.forename: Jian-Wen
authors.initials: JW
authors.lastname: Tan
mesh_terms: D017360:Arabidopsis / Q000187:drug effects*; D027722:Convolvulaceae / Q000737:chemistry*; D008401:Gas Chromatography-Mass Spectrometry; D018525:Germination / Q000187:drug effects*; D010636:Phenols / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology*; D020156:Salicylic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D012639:Seeds / Q000187:drug effects*
chemical_list: D010636:Phenols; D010936:Plant Extracts; D020156:Salicylic Acid