Aqueous two-phase system coupled with ultrasound for the extraction of lignans from seeds of Schisandra chinensis (turcz.) Baill

In this study the potential use of an aqueous two phase system (ATPS) coupled with ultrasound for the extraction of lignans from Schisandra chinensis seeds was evaluated and optimized using response surface methodology (RSM). The main bioactive components, schizandrin (SA), schisantherin A (SAA) and deoxyschizandrin (DSA) were selected as markers. The partitioning behavior of lignans in different salt-types of ATPS was compared. The optimization ATPS of 25% (w/w) (NH4)2SO4 and 19% (w/w) ethanol were selected based on their higher upper phase partitioning coefficient (>74) and the recovery (>93%) for three markers. Using the optimized ATPS solvent, the RMS results showed 20:1 of solvent:solid, 800 W and 61.1 min were the optimal ultrasound assisted extraction conditions, under which 13.10 mg/g SA, 1.87 mg/g SAA and 1.84 mg/g DSA were recovered in the upper phase, whereas the wasted stigmas accumulated in the lower phase. Compared with 80% ethanol (v/v) ultrasonic extraction, similar yields were obtained, but the present method exhibited higher extraction purity for the selective extraction of lignans from S. chinensis seeds.