Seed oil fatty acid patterns of the Aconitum-Delphinium-Helleborus complex (Ranunculaceae)

Abstract

Many members of Ranunculaceae contain unusual fatty acids in their seed oils. This leads to rather typical genus-specific fatty acid patterns or “fingerprints” in these seed oils. The members of the Delphinioideae and/or Helleboroideae, however, do not contain highly unusual fatty acids. Nevertheless, their seed oil fatty acid fingerprints are also fairly typical and genus-specific, and the patterns found are rather consistent throughout several species of one genus. It was found that species of Aconitum do not contain fatty acids with 20 carbon atoms.Delphinium, Consolida, Helleborus, Nigella and others do contain C20 fatty acids. In all Helleborus species, for example, there was a consistent C20 fatty acid pattern of 20:0≪20:1≫20:2>20:3. Species of Nigella and Garidella contain high levels,Helleborus low levels, of 20:2n-6 in their seed oils.Delphinium and Aconitum both contain low levels of 18:3n-3, whereas Helleborus spp. consistently show high levels of this fatty acid. The genus-specific fatty acid patterns found are discussed, and a correlation with the subfamily and tribe affiliation of the genera investigated here is attempted.