Farina flavonoids

Since the first review on flavonoids of the Filicopsida by Swain and Ccx)per-Driver (14), a considerable number of papers have been published on the chemistry and distribution of flavonoids in ferns. The farina flavonoids of gymnogrammoid ferns have been reviewed by WOLLENWEBER (81, 132,141, 245). 

Except for the farina flavonoids on the frond surface of gymnogrammoid ferns almost all the flavones and flavonols occur as glycosides. However, flavone 0-glycosides are far less common in ferns and occur mostly in pteridaceaeous ferns (sensu Coplandi). On the other hand, flavonol 0-glycosides are very common in ferns the most common ones are glycosides of kaempferol (176) and quercetin (196). 

In the Pityrogramma, flavones and flavonols are minor constituents of the farina flavonoids (147,162, 245). In Notholaena and Cheilanthes... 

WOLLENWEBER, E., and V.H. Dietz Flavonoid Patterns in the Farina of Goldenback and Silverback Ferns. Biochem. Syst. Ecol. 8, 21 (1980). 

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