Guaianolide Derivatives from the Invasive Xanthium spinosum L.: Evaluation of Their Allelopathic Potential

Abstract

Ziniolide, xantholide B (11α-dihydroziniolide), and 11β-dihydroziniolide, three sesquiterpene lactones with 12,8-guaianolide skeletons, were identified as volatile metabolites from the roots of Xanthium spinosum L., an invasive plant harvested in Corsica. Essential oil, as well as hydrosol and hexane extracts, showed the presence of guaianolide analogues. The study highlights an analytical strategy involving column chromatography, GC-FID, GC-MS, NMR (1D and 2D), and the hemi-synthesis approach, to identify compounds with incomplete or even missing spectral data from the literature. Among them, we reported the 1H- and 13C-NMR data of 11β-dihydroziniolide, which was observed as a natural product for the first time. As secondary metabolites were frequently involved in the dynamic of the dispersion of weed species, the allelopathic effects of X. spinosum root’s volatile metabolites were assessed on seed germination and seedling growth (leek and radish). Essential oil, as well as hydrosol- and microwave-assisted extracts inhibited germination and seedling growth; root metabolite phytotoxicity was demonstrated. Nevertheless, the phytotoxicity of root metabolites was demonstrated with a more marked selectivity to the benefit of the monocotyledonous species compared to the dicotyledonous species. Ziniolide derivatives seem to be strongly involved in allelopathic interactions and could be the key to understanding the invasive mechanisms of weed.

Abundance of Xanthium spinosum L. along the different land types and its impacts on invaded plant communities in North Shewa Zone, Ethiopia

“…X. spinosum possess hooked spines that can attach to animal coats and clothing, contributing to the dispersal over large areas (Andreani et al, 2016). It is identified as one of the IAPS significantly causing global biodiversity loss (Sylvain et al, 2022). This species exhibits robust adaptability in arid desert areas and is a prevalent malignant IAPS in Xinjiang, China.…”

Effects of Different Degrees of Xanthium spinosum Invasion on the Invasibility of Plant Communities in the Yili Grassland of Northwest China

“…Studying the invasibility of plant communities has theoretical and practical relevance for understanding the mechanisms of alien plant invasion, preventing and controlling invasion by alien plants, and restoring invaded communities [6,7]. Studies have investigated the invasive mechanisms of alien plants (e.g., biological characteristics and interspecific relationships) and the effects of climate or environmental changes on plant invasion, but few studies have focused on the relationship between plant invasion and community invasibility [8,9].…”

“…This species displays strong adaptability, reproductive ability, and competitive ability in its invasiveness, which not only causes agricultural loss and biodiversity reduction but also affects the health of humans and livestock owing to pollen allergies [19]. The thorns on the surface of the involucre of X. spinosum allow it to be easily spread by humans or animals when it attaches to clothing or fur, which can inadvertently spread it over a large area within a short time [9]. In addition, X. spinosum has strong growth and reproductive abilities, a large seed yield, a high germination rate, diverse diffusion media, and rapid spread, and it quickly occupies a large area and inhibits the growth and reproduction of native plants and crops.…”