title: A detailed survey of seed coat flavonoids in developing seeds of Brassica napus L.
abstract: Proanthocyanidins (PAs) are seed coat flavonoids that impair the digestibility of Brassica napus meal. Development of low-PA lines is associated with a high-quality meal and with increased contents in oil and proteins, but requires better knowledge of seed flavonoids. Flavonoids in Brassica mature seed are mostly insoluble so that very few qualitative and quantitative data are available yet. In the present study, the profiling of seed coat flavonoids was established in eight black-seeded B. napus genotypes, during seed development when soluble flavonoids were present and predominated over the insoluble forms. Thirteen different flavonoids including (-)-epicatechin, five procyanidins (PCs which are PAs composed of epicatechin oligomers only) and seven flavonols (quercetin-3-O-glucoside, quercetin-dihexoside, isorhamnetin-3-O-glucoside, isorhamnetin-hexoside-sulfate, isorhamnetin-dihexoside, isorhamnetin-sinapoyl-trihexoside and kaempferol-sinapoyl-trihexoside) were identified and quantified using liquid chromatography coupled to electrospray ionization-mass spectrometry (LC-ESI-MS(n)). These flavonol derivatives were characterized for the first time in the seed coat of B. napus, and isorhamnetin-hexoside-sulfate and isorhamnetin-sinapoyl-trihexoside were newly identified in Brassica spp. High amounts of PCs accumulated in the seed coat, with solvent-soluble polymers of (-)-epicatechin reaching up to 10% of the seed coat weight during seed maturation. In addition, variability for both PC and flavonol contents was observed within the panel of eight black-seeded genotypes. Our results provide new insights into breeding for low-PC B. napus genotypes.
authors.affiliation: UMR118 INRA, Agrocampus Ouest, Université Rennes 1, Amélioration des Plantes et Biotechnologies Végétales, BP35327, 35653 Le Rheu Cedex, France.
authors.forename: Bathilde
authors.initials: B
authors.lastname: Auger
authors.forename: Nathalie
authors.initials: N
authors.lastname: Marnet
authors.forename: Véronique
authors.initials: V
authors.lastname: Gautier
authors.forename: Alessandra
authors.initials: A
authors.lastname: Maia-Grondard
authors.forename: Françoise
authors.initials: F
authors.lastname: Leprince
authors.forename: Michel
authors.initials: M
authors.lastname: Renard
authors.forename: Sylvain
authors.initials: S
authors.lastname: Guyot
authors.forename: Nathalie
authors.initials: N
authors.lastname: Nesi
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Routaboul
mesh_terms: D029688:Brassica napus / Q000737:chemistry* / Q000235:genetics; D002392:Catechin / Q000032:analysis; D002853:Chromatography, Liquid; D005419:Flavonoids / Q000032:analysis*; D044948:Flavonols / Q000032:analysis; D005838:Genotype; D007700:Kinetics; D044945:Proanthocyanidins / Q000032:analysis; D012639:Seeds / Q000737:chemistry* / Q000254:growth & development*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D005419:Flavonoids; D044948:Flavonols; D044945:Proanthocyanidins; D002392:Catechin