Planta Med 2008; 74 - PC51
DOI: 10.1055/s-0028-1084569

Preparative isolation of Alkannin/Shikonin derivatives by High-Speed Counter-Current Chromatography

AN Assimopoulou 1, S Sturm 2, H Stuppner 2, VP Papageorgiou 1
  • 1Organic Chemistry Laboratory, Chemical Engineering Department, Aristotle University of Thessaloniki, 54124Thessaloniki, Greece
  • 2Institut für Pharmazie, Abteilung Pharmacognosie, Leopold-Franzens-Universität Innsbruck, Innrain 52, A-6020 Innsbruck, Austria

Alkannin, Shikonin (A/S) and their derivatives are secondary metabolites biosynthesized in the roots of several Boraginaceous species and are also produced through plant tissue cultures. The chiral compounds A/S are potent pharmaceutical substances with a wide spectrum of biological activities like wound healing, antimicrobial, anti-inflammatory, anticancer and antioxidant [1,2]. Because of the important biological properties and uses of A/S and their derivatives in pharmaceuticals, as well as food colorants, high-purity preparations containing A/S and derivatives are of great interest. As shown in our previous papers most of the commercial samples of A/S and their derivatives, prepared either from natural products, or by synthesis or plant tissue cultures, are not purified since contain mainly monomeric, oligomeric A/S derivatives and other metabolites [3], and thus need further purification.

High-speed counter-current chromatography (HSCCC) is a form of liquid-liquid partition chromatography, where solute separation is based on partitioning between the two immiscible liquid phases. The stationary phase is retained in the column with the aid of a centrifugal force field and gravity, eliminating irreversible adsorption of samples onto the solid support used in conventional column chromatography. HSCCC has been used for separation and purification of bioactive compounds from natural products, such as alkaloids, hydroxyanthraquinones, flavonoids etc.

Aim of the present study was to introduce an efficient HSCCC method for separation and purification of A/S derivatives from samples containing A/S derivatives and to apply a reliable HPLC-DAD-MS method for identification of HSCCC fraction constituents. Purity of fractions separated by HSCCC was compared with those obtained by the traditionally used method, column chromatography. It is shown that the purity of isolated monomeric alkannin/shikonin is greater by HSCCC than column chromatography separation of commercial A/S samples.

References: 1. Papageorgiou, V.P. et al. (1999) Angew Chem Int. Ed. 38: 270–300.

2. Papageorgiou, V.P. et al. (2006) Curr Org Chem 10: 2123–2142.

3. Assimopoulou, A.N. et al. (2008) Biomedical Chromatography 22: 173–190.