JOHNSON, EMANUEL L.1*, WALTER F. SCHMIDT2, STEPHEN D. EMCHE1, MAGDI M. MOSSOBA3, and STEPHEN M. MUSSER3. 1USDA ARS ACSL, BARC-W, Beltsville, MD 20705; 2ECL Bldg 12 USDA ARS BARC-W, Beltsville, MD 20705; 3IBB FDA HFS-717 200 C St. S.W., Washington, D.C. 20204. - Kaempferol rhamnoglucoside, a new flavonol from Amazonian coca (Erythroxylum coca var. ipadu).
Erythroxylum coca var. ipadu Plowman (E. c. var.
ipadu) was harvested from cultivated fields in the Amazonian
region of Colombia, South America, to determine: (a) their leaf
flavonoid profile; (b) their similarity or difference to those present
in our living collection of the taxon and (c) the usefulness of the
flavonoids as chemotaxonomic markers for the taxon. High performance
liquid chromatography was used to separate the flavonoids while
spectra analyses were used for their identification. A new flavonol
was found and isolated from leaf tissue of Amazonian field-grown coca
(Erythroxylum coca var. ipadu Plowman) that has not been
reported. The structure of the flavonol was determined to be
kaempferol 4'-O-rhamnoglucoside. The array of flavonoids present in
E. c. var. ipadu is indicative and consistent with
ancestralship to E. c. var. coca. The new flavonol is
useful as a chemotaxonomic marker for the taxon.
Key words: Amazonian coca, Erythroxylum coca, flavonol, kaempferol rhamnoglucoside