CHEMISCHE RASSEN BEI ALKALOIDPFLANZEN

Abstract

Secondary metabolites but not primary products (e. g. amino acids, nucleic acids) are used as markers to characterize infraspecific chemical taxa in the plant kingdom. About SO years ago the term secondary metabolites was introduced by F. Czapek in his essay on alkaloids. The role of secondary constituents (including alkaloids) in general metabolism of plants is controversial. Some aspects are critically reviewed.

The importance of chemical races of selected alkaloids containing plant species is discussed from the pharmaceutical point of view. An interesting thoroughly studied example is Solanum dulcamara L. As a model for the possible origin of chemical races-crossing experiments with Datura ferox L. and Datura stramonium L. are described. The different geographical and chemical races of Duboisia are covered. The chemotaxonomical problems of Section Oxytona (Genus Papaver) and especially of the thebaine containing species Papaver bracteatum Lindl. are discussed. Apparently chemical races are lacking in the pharmaceutically important indole alkaloids containing genera of Strychnos, Rauwolfia and Catharanthus. Lysergic acid derivatives are mainly produced by Claviceps paspali and Claviceps purpurea which might be divided into different chemovarieties. After irradiation with UVAight and treatment with chemical mutagens of various Claviceps strains mutants were selected which differed markedly in their alkaloid spectrum compared with the wild type. This is a striking example of infraspecific differentiation due to manipulation of the genetic material.