Preparative separation and purification of deoxyschizandrin from Schisandrae Sphenantherae Fructus by high-speed counter-current chromatography oleh Xin-Ying Li, Mei Yang, Jie-Yun Huang, Xiao-Xue Yu, Min-Qian Zhao, Zhi-Kun Liang, Zhi-Sheng Xie, Xin-Jun Xu