96. Separation and Purification of (-)Schisandrin B from Schisandrin B Stereoisomers.

Luk KF[1], Ko KM[2], Ng KM[3].

[1] Bioengineering Graduate Program, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong.
[2] Department of Biochemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong.
[3] 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.