The flavonoids ofMitella,Bensoniella, andConimitella(Saxifragaceae)

摘要

Flavonoid profiles have been determined for 16 species ofMitellaand for the two monotypic genera,BensoniellaandConimitella. With a single exception the profiles are based upon the flavonols kaempferol, quercetin, and myricetin. The flavanone eriodictyol was seen in two Japanese species ofMitella. The flavonols exist as a series of 7-O-mono-, 3-O-mono-, 3-O-di-, and 3-O-triglycosides, although not all levels of glycosylation occur in each taxon. 7-O-Methylkaempferol and 7-O-methylquercetin were found inM.nudaandM.diphylla;M.nudaalso has isorhamnetin. The flavonoids ofM.nudaare unique in the genus, but otherwise the distribution of the pigments does not offer support for Rydberg's view of the species being assigned to four genera or Rosendahl's view thatMitellacomprises two sections. The flavonoid profile ofBensoniella oregonaclearly distinguishes it fromMitella. Flavonoid data forConimitella williamsiiagree in general with those of a moderately advanced species ofHeucherain agreement with Savile's views on the origin ofConimitella. Our results are discussed in terms of the recent finding thatConimitellaandMitellaform natural hybrids.