The preparative high – performance liquid chromatography is especially profitable technique of separation and isolation of a usable amount of substances from different complicated mixtures. This work presents the optimal conditions of ramentaceone and plumbagin separation and isolation in a way allowing simultaneous separation with maximal selectivity of this naphthoquinones and ballast substances contained in chloroform extracts from plants D.aliciae and D.capensis using Revese Phase – High Performace Liquid Chromatography technique and isocratic elution.
Naphthoquinones were separated on C18 chromatographic columns using the different varieties of composition of the mobile phase like: water with addition of acetonitrile, methanol, tetrahydrofuran, acetic acid, trifluoroacetic acid, to formulate the optimal conditions to obtain these substances in preparative scale. For separation of substances in preparative scale gradient elution is unprofitable. It enlarges costs and technical complication, in relation to isocratic conditions. The compounds of plant extract which strongly interacted with the stationary phase were released from the HPLC column using backflush instead of step elution.
In this research ramentaceone and plumbagin were obtained in a crystalline form with high purity using optimal conditions of liquid extraction, crystallization and recrystallization. The column productivity and purity of metabolites in a maximum level of HPLC column overloading conditions were defined.
Acknowledgements: State Commitee for Scientific Research, Grant No N N523 4531 33.
