FLAVONOID VARIATION IN EURASIAN SEDUM AND SEMPERVIVUM

Flavonoids from vegetative parts of 29 species of Eurasian Sedum, Sedu m meyeri-johannis from central East Africa, 34 species of Sempervivum, and Jovibarba heuffelii have been identified after acid hydrolysis. T en flavonoid aglycones were detected, i.e. kaempferol, herbacetin, sex angularetin, quercetin, gossypetin, corniculatusin, isorhamnetin, limo citrin, myricetin, and possibly hibiscetin. Quantitative flavonoid dat a were obtained by gas chromatography after trimethylsilylation and we re studied with multivariate data analysis methods. Principal componen ts analysis of the whole data set distinguishes Sedum and Sempervivum as separate groups. Flavonoid variation in Sempervivum is minimal (kae mpferol is the principal flavonol of all species), which reflects the morphological uniformity of the genus and similarity in ecological pre ference of the species. By contrast, Eurasian Sedum contains a much wi der range of flavonols and shows a high degree of parallel evolution ( notably 8-hydroxylation and 8-O-methylation), which seems to mirror th e enormous morphological and cytological variation present in this tax on. The recognition of groups in Sedum by principal components analysi s of flavonoid data partially supports the infrageneric classification based on biosystematic data.