Liquid chromatographic analysis of supercritical carbon dioxide extracts of Schizandra chinensis

Six major lignans (schizandrin, gomisin A, deoxyschizandrin, γ-schizandrin, gomisin N, wuweizisu C) in the caulomas and leaves of Schizandra chinensis (Turcz.) Baill., and cinnamic acid in the leaves of the plant, were quantitatively analysed by high-performance liquid chromatography in reversed-phase mode with UV detection. Resolution of the determined lignans was evaluated for two multistep gradients applied. Samples for HPLC analysis were prepared by extraction with supercritical carbon dioxide at pressures of 20–27 MPa and temperatures of 40–60 °C. Kinetics of the extraction of individual components was measured and simulated with a model.