Philip Sheridan, Meadowview Biol. Research Station and Dept. of Biol.
Sciences, ODU and
Robert Griesbach*, Floral and Nursery Plant Research, USDA Beltsville.
The flavonols quercetin and kaempferol have been identified in the genus Sarracenia by previous workers. We were interested in determining the anthocyanins in leaves and flowers of this genus to gain a fuller understanding of the anthocyanin and flavonoid metabolic pathway in this pitcher plant genus. We expected to find the anthocyanidins cyanidin and pelargonidin since these are the anthocyanidins generally produced from the dihydro precursors of quercetin and kaempferol. Leaf and petal tissue was extracted in acidified methanol, taken to dryness in a rotary evaporator, and redissolved in acidified methanol. Samples were then eluted on an HPLC, coeluted with standards, and finally acid hydrolyzed to determine anthocyanidin and sugar moieties. Sarracenia species generally only produced cyanidin in leaves and petals. Glucose and galactose were the only sugars attached to the anthocyanidins. Somewhat surprisingly, S. purpurea petals contained both delphinidin and cyanidin. Delphinidin represents a new anthocyanidin for the genus and offers the possibility of breeding for blue flower color in this horticulturally valuable genus. The absence of pelargonidin indicates that further work on the enzymatic processes within the Sarracenia anthocyanin pathway are warranted.