Luk KF, Ko KM, Ng KM.
 Bioengineering Graduate Program, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong.
 Department of Biochemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong.
 Department of Chemical Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong.
Schisandrin B (Sch B), consisting of a mixture of its stereorisomers, namely (-)Sch B and (+/-)gamma-schisandrin, is the most abundant and biologically active dibenzocyclooctadiene lignan present in Fructus Schisandrae (FS). The objective of this study is to develop a process for large-scale separation and purification of a single stereoisomer of Sch B, (-)Sch B. which offers the highest desirable bioactivities. To this end, a crystallization-based separation and purification process has been conceptualized. Bench-scale crystallization experiments guided by experimental solid-liquid equilibrium phase diagrams were performed to verify process feasibility. A (-)Sch B product with a purity of 98.5 wt\% and a (+/-)gamma-schisandrin-enriched product with a purity of 65.0 wt\% were obtained. The (-)Sch B product caused a 32\% increase in cellular glutathione level and the (+/-)gamma-schisandrin-enriched product a 26\% increase, indicating a potentially more efficacious pharmaceutical preparation.