Chemotaxonomy of Portuguese Ulex: Quinolizidine alkaloids as taxonomical markers

Six species of Ulex L. in a total of nineteen populations were investigated as to their content in quinolizidine alkaloids. Seventeen known alkaloids were detected by GC–EIMS and quantification of the seven more abundants alkaloids in all populations was done by GC. Principal component analysis of these data allowed the definition of chemotypes for five of the species and the recognition of hybrids. N-Methylcytisine, cytisine, and jussiaeiines A, C and D are recognized as markers of this genus in Portugal. Six species of Portuguese Ulex L. in a total of nineteen populations were studied by GC–EIMS as to their content in quinolizidine alkaloids. Sparteine, β-isosparteine, jussiaeiine A, N-methylcytisine, cytisine, 5,6-dehydrolupanine, rhombifoline, lupanine, jussiaeiine B, N-formylcytisine, N-acetylcytisine, anagyrine, jussiaeiine C, jussiaeiine D, pohakuline, baptifoline, and epibaptifoline were detected. Analysis of the chromatograms showed that the chemical profile of all species was mainly composed of N-methylcytisine, cytisine, anagyrine, and jussiaeiines A, B, C and D. Therefore a quantification study of these alkaloids in all the populations studied was done by GC. These data were then submitted to cluster analysis and principal component analysis, which allowed the definition of five chemotypes and the recognition of hybrids. N-methylcytisine, cytisine, and jussiaeiines A, C and D are recognized as markers of this genus in Portugal.