Virginia creeper

Virgin s bower Clematis virgin ana) Virginia creeper Parthenocissus)... 

The grape is a seasonal plant. Moreover, conversion of ascorbate to tartrate, as noted above, is limited to certain stages of growth and development. EflForts to find an alternative species of Vitaceae more amenable to research led us to Virginia Creeper (Parthenocissus quinque-folia). In a controlled environment, this plant retains its leaves and continues to lengthen its vines indefinitely, an ideal system for study of Vitaceae-type ascorbic acid metabolism on a year-around basis. 

Virginia Creeper leaves were fed L-ascorbic acid with C in Cl, C4, C5, or C6 or on C6 (14). In each experiment, three compound leaves from the fifth position behind the tip of the vine were used. After a 24-h metabolic period, the distribution of radioisotope was determined (Table III). As in the grape, l-[1- C]- and l-[4- C]ascorbic acid produced carboxyl labeled tartaric acid. Virutally no radioisotope appeared in tartaric acid from the other l-[5- C]-, l-[6- C]-, or l-[6- H]ascorbic acid. The larger amount of C02 released by L-[l- C]ascorbic acid labeled leaves has been confirmed in subsequent studies. 

Table III. L-Ascorbic Acid Catabolism in Virginia Creeper (Metabolic Period, 24 h)...

Creeper. The latter, which failed to produce labeled tartaric acid in grape or Virginia Creeper, produced carboxyl labeled tartaric acid in geranium. 

Recently a study of the D-glucose to L-ascorbic acid conversion in Virginia Creeper was completed in which Cl, C6, HI, or H6 labeled... 

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