Abstract:In this study, a magnetic stirring assisted supercritical CO2 extraction method was established and applied to the extraction of eight lignans from the fruit of Schisandra chinensis. The target analytes were separated and determined by high performance liquid chromatography (HPLC). Specifically, supercritical CO2 was used as extraction solvent, the sample was pre-impregnated with ethanol solution, and the contact between samples and supercritical CO2 was promoted by magnetic stirring to improve mass transfer efficiency. Then, various factors affecting the extraction efficiency of lignans were optimized, and compared with the traditional methods. The experimental results showed that the good linear relationship for analytes was obtained in the linear range (r>0.9998). The limit of detection and limit of quantification were 21.30~990.20 ng/mL and 60.80~2992.80 ng/mL, respectively. The spiked recoveries were between 75.00% and 97.78%. The analysis results were satisfactory. Compared with other methods, the extraction yield obtained by this method was significantly higher than that obtained by microwave extraction and thermal reflux extraction, and comparable to that obtained by the pharmacopoeia method. Although a small amount of organic solvent was used in the extraction process, the ratio of solid to liquid was only 1:2, which is 1/25~1/50 of other methods. This method has the advantages of large sample handling capacity, simple operation, environmental protection and high extraction efficiency, and certain potential in industrial production and application. It can be used for the extraction and separation of lignans in traditional Chinese medicine.
