A new method for the separation of anthraquinone glycosides

Several methods have been used in the past for the isolation of the anthraquinone glycosides present in plants. These methods utilized solvents such as water and alcohol or mixtures of these. In addition to a partial hydrolysis of the glycosides other interfering substances such as sugars, starches and gums were also extracted, which made a clean cut separation impossible. The method described in this thesis solves these problems by rendering the glycosides insoluble in chloroform and then removing,stepwise, the interfering consituents and, in turn, separates the aglycones from the glycosides in pure form. The method makes use of the fact that the aglycones are chloroform soluble, whereas the glycosides are insoluble in this solvent. A new method for preserving chromatograms is also presented. Chromatographic separation indicates possibly two new glycosides in Senna.