Arboreous fruit of Schisandra chinensis Baillon, Schisandra Fruit (SF), is a crude drug used in Japanese traditional Kampo medicine. The marker compounds of SF for quality control are lignans, such as schizandrin (Sz) and gomisin A (GmA). Kampo formulation containing SF is usually prepared as decoctions in the dosage form of whole crude drug (W), as its size is small enough to measure using a spoon. However, in some traditional books, it has been described that SF must be used in the dosage form of crushed or cut pieces (Cr). In this study, we evaluated the transferring ratio of lignans from SF to the decoction, and the stability and taste of the decoctions of shoseiryuto (SST) and ninjin'yoeito (NYT) using each dosage form, i.e., Cr and W, of SF. The transferring ratio of Sz and GmA was significantly higher in the decoction prepared with the Cr form than that prepared using the W form in both SST and NYT. The concentration of Sz and GmA in the decoctions was stable when maintained at 4 °C for 35 days. The taste of SST decoction prepared using the Cr form was more acidic, harsher, and bitterer than SST decoction prepared using the W form, and the taste of NYT decoction prepared using the Cr form was harsher than NYT decoction prepared using the W form. In conclusion, when SF is used in Kampo prescription, crushing the fruits and seeds can increase its effectiveness.
Keywords: Decoction; Gomisin A; Kampo medicine; Schisandra fruit; Schizandrin.