[Study on allelopathic effect of ginseng root exudates against its root callus].

OBJECTIVE: To study the effect of ginseng root exudates against its root callus and provide theoretic basis for allelopathic mechanism and continuous cropping obstacle. METHODS: We cultured ginseng root callus with MS culture medium whose concentration was equal to soil concentration of 80, 40, 20, 10, 5 gDW/mL and chose the optimum concentration for further study on allelopathic effect of ginseng root exudates against its root callus content of MDA and DNA. The root callus which was treated at different time was observed with paraffin slice method. RESULTS: The content of MDA increased quickly after cultured one day and was significantly different from control (P < 0.01), then gradually reduced. The content of DNA gradually reduced with culturing time and was dramatically different in the treatment (P < 0.01). The nucleolus gradually decreased, disaggregated and disappeared. CONCLUSION: The allelopathy of ginseng root exudates can destroy ginseng root callus membranous function and influence the amount of nucleolus. The cell division and differentiation are checked and the growth of ginseng root callus is inhibited.

[Preparative separation of gentiopicrin from Gentiana scabra bunge by high speed counter current chromatography].

OBJECTIVE: High speed counter current chromatography was successfully applied to the preparative separation of the component of Gentiana scabra Bunge. METHOD: Gentiopicrin was obtained by preparative HSCCC with two phase solvent system com-posed of chloroform-methanol-tert-butylmethyl-water (5:4:2:4). The mobile phase is the lower phase and operated at a flow-rate of 2.0 ml/min, while the apparatus rotated at 820 r/min. RESULT: High performance liquid chromatogra phic analysis of gentiopicrin was over 96.68%. CONCLUSION: HSCCC is a useful method for the separation of natural products.