Complexation of sesquiterpene lactones with cyclodextrins: synthesis and effects on their activities on parasitic weeds. Issue 31 (26th July 2017)

• Record Type: Journal Article
• Authors: Cala, Antonio; Molinillo, José M. G.; Fernández-Aparicio, Mónica; Ayuso, Jesús; Álvarez, José A.; Rubiales, Diego; Macías, Francisco A.
• Is Part Of: Organic & biomolecular chemistry. Volume 15:Issue 31(2017)
• Page Start: 6500
• Page End: 6510
• Publication Date: 2017-07-26
• Subjects: Chemistry, Organic -- Periodicals; Bioorganic chemistry -- Periodicals; Chemistry, Physical organic -- Periodicals; 547
• DOI: 10.1039/c7ob01394a
• Languages: English
• ISSNs: 1477-0520

Abstract

Abstract : Cyclodextrin complexes were prepared by the kneading and coprecipitation methods; then theoretical complexes were calculated and different bioassays were carried out. Abstract : Allelochemicals are safer, more selective and more active alternatives than synthetic agrochemicals for weed control. However, the low solubility of these compounds in aqueous media limits their use as agrochemicals. Herein, we propose the application of α-, β- and γ-cyclodextrins to improve the physicochemical properties and biological activities of three sesquiterpene lactones: dehydrocostuslactone, costunolide and (−)-α-santonin. Complexation was achieved by kneading and coprecipitation methods. Aqueous solubility was increased in the range 100–4600% and the solubility–phase diagrams suggested that complex formation had been successful. The results of the PM3 semiempirical calculations were consistent with the experimental results. The activities on etiolated wheat coleoptiles, Standard Target Species and parasitic weeds were improved. Cyclodextrins preserved or enhanced the activity of the three sesquiterpene lactones. Free cyclodextrins did not show significant activity and therefore the enhancement in activity was due to complexation. These results are promising for applications in agrochemical design.