Ultrasound-Assisted Aqueous Two-Phase System for Extraction and Enrichment of Zanthoxylum armatum Lignans

In the study, an aqueous two phase system (ATPS) coupled with ultrasound was employed to extract lignans from Zanthoxylum armatum. Three standard lignans, namely (-)-fargesin, sesamin and L-asarinin, were used as marker compounds, and extraction was optimized and projected by response surface methodology (RSM) and artificial neural network (ANN). The optimal condition for ATPS with 20% n-propanol and 24% (NH4)2SO4 coupled with ultrasonic-assisted extraction including a solvent to solid ratio of 15:1, a temperature of 40 °C, and a treatment time of 55 min was obtained. Under the condition, the yield of (-)-fargesin increased 15.12%, and the purities of (-)-fargesin, sesamin and L-asarinin reached 2.222%, 1.066%, and 1.583%, with an increase of 44.38%, 25.70%, and 26.34% compared to those extracted with 95% ethanol, respectively. Coefficient of the determined (0.9855) and mean squared error (0.0018) of ANN model suggested good fitness and generalization of the ANN. Taken together, the results showed that ultrasonic-assisted ATPS can be a suitable method for extraction and enrichment of lignans from Z. armatum.