The flavonoids of Arnica frigida and A. louiseana (Asteraceae)

Abstract

Forty-six populations within the Arnica frigida Meyer ex Iljin – louiseana Farr complex were examined for flavonoid content. Seven glycosides were isolated and six identified. Members of this complex were found to produce primarily quercetin and kaempferol 3-O-glycosides. Flavonoid profiles obtained from A. frigida ssp. frigida were the most diverse and in some cases the most depauperate. Within this taxon, flavonoid diversity appears to have accompanied high morphological variability. The occurrence of flavonoid-depauperate plants in unglaciated Alaska suggests that flavonoids are of value in identifying refugia. Flavonoid profile similarities between A. frigida ssp. frigida and A. frigida ssp. griscomii corroborate morphological evidence as to the close affinity between these two taxa.