title: High-speed counter-current chromatography for the study of defense metabolites in wheat. Characterization of 5,6-O-methyl trans-aconitic acid.
abstract: High-speed counter-current chromatography (HSCCC) methods were developed for the study of induced defense metabolites in wheat (Triticum aestivum) against powdery mildew (Blumeria graminis f. sp. tritici). A single HSCCC purification step afforded extraction of mg-quantities of an induced compound with antifungal activity. Subsequent LC-MS and NMR analyses have led to the characterization of 5,6-O-methyl trans-aconitic acid, the first such report of this compound in a plant species. The inducible nature of aconitic acid was evidenced by comparing the metabolite profiles of leaf extracts from plants treated or not with soluble silicon and infected or not with powdery mildew. In a second step, dual-mode HSCCC was used to enhance the separation of other forms of aconitic acid in wheat. Based on these results, it was concluded that 5,6-O-methyl trans-aconitic acid plays an important role as a defense molecule in wheat plants and that HSCCC is a powerful separation method for purifying such compounds from complex plant-pathogen interactions.
authors.affiliation: Département de Phytologie, Université Laval, Sainte-Foy, Que., Canada G1K 7P4.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Rémus-Borel
authors.forename: Nancy
authors.initials: N
authors.lastname: Shallow
authors.forename: David J
authors.initials: DJ
authors.lastname: McNally
authors.forename: Caroline
authors.initials: C
authors.lastname: Labbé
authors.forename: Richard R
authors.initials: RR
authors.lastname: Bélanger
mesh_terms: D000156:Aconitic Acid / Q000031:analogs & derivatives* / Q000032:analysis / Q000737:chemistry; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003377:Countercurrent Distribution / Q000379:methods*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D014908:Triticum / Q000378:metabolism*
chemical_list: C513596:5,6-O-methylaconitic acid; D000156:Aconitic Acid