Contribución al estudio fitoquímico de los colorantes presentes en hojas de Arrabidaea Florida D.C.

Abstract

The species Arrabidaea florida DC. (Bignoniaceae), known as Om or Cudi, is widely used as a dye by the indigenous communities of the Amazon trapeze. Considering that there are no phytochemical studies on the species, in this work the chemical study of the predominant fixed metabolites in the colorant precipitate obtained by fermentation of the aqueous extract of dry leaves was carried out, and the components retained in cotton fibers stained with leaves of the species were analized. Separation and purification was performed by discontinuous liquid-liquid fractionation, column chromatography and exclusion, allowing to obtain in the fractions of medium and high polarity the flavones: apigenin, luteolin, acacetin, 6-methoxyluteolin, and scutellarein, and 3-deoxythianocyanes: 3',4',6,7-tetrahydroxy-5-methoxyflavylium, 4',6,7-tetrahydroxy-5-methoxyflavylium and 6,7-tetrahydroxy-4',5-dimethoxyflavylium, which we named 3'-hydroxyarrabidine, arrabidine and carajurine respectively. Compounds were analyzed and identified using two high-performance liquid chromatography (HPLC-DAD) systems, with a database of HPLC reference compounds. HPLC-DAD analysis of the dye extract obtained from cotton fibers stained with Arrabidaea florida revealed as main components carajurine, arrabidine and 3'-hydroxyarrabidine and the flavones luteolin, acacetin and apigenin. The comparison of fixed and volatile metabolites of this species with Arrabidaea chica was also performed, with a high correspondence between the two species varying in the percentages in which they are present.