Analysis of Schisandra chinensis and Schisandra sphenanthera

Wuweizi (Fructus Schisandrae) is classified in traditional Chinese medicine as a superior drug, and has been used for thousands of years. Modern pharmacological research has demonstrated that most of the biological actions and pharmacological effects of Wuweizi can be attributed to its lignan constituents, particularly the dibenzocyclooctadiene-type lignans, which can lower the serum glutamate-pyruvate transaminase (SGPT) level, inhibit platelet aggregation, and show antioxidative, calcium antagonism, antitumor-promoting, and anti-HIV (human immunodeficiency virus) effects. The dried ripe fruits of both Schisandra chinensis and Schisandra sphenanthera have long been used as Wuweizi, although their chemical constituents and contents of the bioactive components are quite different. Since 2000, they have been accepted as two different crude drugs, Bei-Wuweizi and Nan-Wuweizi, respectively, by the Chinese Pharmacopoeia. In order to provide a useful reference for good quality control of Wuweizi, many studies on the chemical constituents, pharmacological effects, identification and quality control methods of the two drugs have been reported in the literature and are summarized herein. Particular attention was given to the different methodologies developed for the qualitative and quantitative analysis of the major bioactive lignans. In our opinion, thin-layer chromatography (TLC) is the most simple and convenient method for identification of these two crude drugs, and high-performance liquid chromatography with UV detection (HPLC-UV) is the preferred method for quantitative analysis based on the bioactive lignans. Some newly developed methods, particularly hyphenated chromatographic-analytical techniques, are effective in determination of the lignans that occur in low content and those difficult to be fully separated with HPLC.