Purification of lignans from Schisandra chinensis fruit by using column fractionation and supercritical antisolvent precipitation

This study examined the use of ultrasonic-assisted extraction (UAE) coupled with column chromatography (CC) and supercritical antisolvent (SAS) precipitation in purifying five lignans from the dried fruit of Schisandra chinensis. Column fractionation of the ultrasonic extracts and SAS precipitation of the column elution resulted in a ten- and three-fold increase of the five lignans, respectively. Experimental data showed that the concentrations of the five lignans increased from 26.14 mg g−1 in the extraction to 581.85 mg g−1 in the effluent after SAS precipitation with a recovery of 84%. The effluent contained 145.32 mg g−1of schisandrol B, 56.65 mg g−1of schisandrin A, 66.38 mg g−1 of γ-schisandrin, 266.70 mg g−1 of gomisin N, and 46.80 mg g−1of schisandrin C. In addition, our experimental results from a response surface method designed SAS precipitations for the enhancement of the purity of the five lignans, showed that time and carbon dioxide flow rate are significant in altering the purity and the recovery. This work demonstrated that the five lignans of Schisandra chinensis were successfully purified by using the SAS process.