title: Zealactones. Novel natural strigolactones from maize.
abstract: In the root exudate and root extracts of maize hybrid cv NK Falkone seven putative strigolactones were detected using UPLC-TQ-MS-MS. All seven compounds displayed MS-MS-fragmentation common for strigolactones and particularly the presence of a fragment of m/z 97 Da, which may indicate the presence of the so-called D-ring, suggests they are strigolactones. The levels of all these putative strigolactones increased upon phosphate starvation and decreased upon fluridone (carotenoid biosynthesis inhibitor) treatment, both of which are a common response for strigolactones. All seven compounds were subsequently isolated with prep-HPLC-MS. They all exhibited Striga hermonthica seed germination inducing activity just as the synthetic strigolactone analog GR24. The structure of two of the seven compounds was elucidated by NMR spectroscopy as: methyl (2E,3E)-4-(3,3-dimethyl-5-oxo-2-(prop-1-en-2-yl)tetrahydrofuran-2-yl)-2-(((4-methyl-5-oxo-2,5-dihydrofuran-2-yl)oxy)methylene)but-3-enoate (two diastereomers 1a and 1b). Strigolactones (1a/b) are closely related to the methyl ester of carlactonoic acid (MeCLA) and heliolactone. However, they contain a unique 4,4-dimethyltetrahydrofuran-2-one motif as the "A-ring" instead of the classical (di)methylcyclohexene. Because these compounds were isolated from maize (Zea mays) we called them "zealactone 1a and 1b". The implications of this discovery for our view on strigolactones and their biosynthesis are discussed.
authors.affiliation: Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors.forename: Tatsiana V
authors.initials: TV
authors.lastname: Charnikhova
authors.affiliation: Syngenta Crop Protection AG Research Chemistry, Schaffhauserstr. 101, 4332 Stein, Switzerland.
authors.forename: Katharina
authors.initials: K
authors.lastname: Gaus
authors.affiliation: Syngenta Crop Protection AG Research Chemistry, Schaffhauserstr. 101, 4332 Stein, Switzerland.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Lumbroso
authors.affiliation: Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: Sanders
authors.affiliation: Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Vincken
authors.affiliation: Syngenta Crop Protection AG Research Chemistry, Schaffhauserstr. 101, 4332 Stein, Switzerland.
authors.forename: Alain
authors.initials: A
authors.lastname: De Mesmaeker
authors.affiliation: Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors.forename: Carolien P
authors.initials: CP
authors.lastname: Ruyter-Spira
authors.affiliation: Syngenta Crop Protection AG Research Chemistry, Schaffhauserstr. 101, 4332 Stein, Switzerland.
authors.forename: Claudio
authors.initials: C
authors.lastname: Screpanti
authors.affiliation: Laboratory of Plant Physiology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands. Electronic address: h.j.bouwmeester@uva.nl.
authors.forename: Harro J
authors.initials: HJ
authors.lastname: Bouwmeester
mesh_terms: D015107:4-Butyrolactone / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D018525:Germination / Q000187:drug effects; D007783:Lactones / Q000737:chemistry* / Q000302:isolation & purification; D015394:Molecular Structure; D053147:Plant Exudates / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry*; D012639:Seeds / Q000187:drug effects; D034362:Striga / Q000187:drug effects; D053719:Tandem Mass Spectrometry; D003313:Zea mays / Q000737:chemistry*
chemical_list: D007783:Lactones; D053147:Plant Exudates; D015107:4-Butyrolactone
keywords: Maize (Zea mays); NMR; Prep-HPLC-MS; Seed germination; Striga hermonthica (Orobanchaceae); Strigolactones; UHPLC-MS-MS; Zealactone