Genetic Discrimination between Catharanthus roseus Cultivars by Metabolic Fingerprinting Using $^1H$ NMR Spectra of Aromatic Compounds

When whole cell extracts are subjected to proton nuclear magnetic resonance spectroscopy $(^1H\;NMR)$, metabolite profiles are generated that contain overlapping signals of the majority of compounds within the extract. In order to determine whether pattern recognition based on the metabolite profiles of higher plants is able to genetically discriminate between plants, we analyzed leaf samples of eight cultivars of Catharanthus roseus by $^1H$ NMR. Hierarchical dendrograms, based on the principal component analysis of the $^1H$ NMR total, aliphatic, carbohydrate, and aromatic region data, revealed possible relationships between the cultivars. The dendrogram based on the aromatic region data was in general agreement with the genetic relationships determined by conventional DNA fingerprinting methods. Secologanin and polyphenols were assigned to the signals of the $^1H$ NMR spectra, and contributed most profoundly to the discrimination between cultivars. The overall results indicate that the genetic relationships between C. roseus cultivars are reflected in the differences of the aromatic compounds in the leaves.