Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Recovery, isolation and preliminary structural investigation of germination stimulants produced by Vigna unguiculata Walp. cv. Saunders Upright.

Abstract

Germination stimulants of the seed of the scrophulariaceous root parasites Alectra vogelii, Striga asiatica and Striga gesnerioides were recovered from the nutrient solution of Vigna unguiculata root cultures. Stimulants were quantitatively adsorbed on the macroreticular porous polymer resin XAD-4. Desorption with a methanol gradient in water released these stimulants from the resin. Droplet-countercurrent-chromatography (DCCC), gel-permeation and HPLC constituted an effective combination of techniques for the separation and isolation of the germination inducing substances. Four chromatographically different active compounds were isolated and the structure of one was tentatively identified as a cyclic molecule consisting of a xanthine, an unsaturated C12-carboxylic acid and a dipeptide of glycine and aspartic acid.