Aqueous two-phase extraction of phenolic compounds from Sedum dendroideum with antioxidant activity and anti-proliferative properties against breast cancer cells

Abstract

Sedum dendroideum, a traditional medicinal plant, has a wide variety of pharmacological activities, attributed to phenolic compounds. Despite that there are several methods available for the extraction of phenolic compounds, their use has several disadvantages, evidencing the need for the development of alternative methods. In this study, ethanol-salt aqueous two-phase systems (ATPS) were employed for the extraction of phenolic compounds from S. dendroideum. The effect of different system parameters on the partition of phenolic compounds were studied, including the volume ratio (VR), tie-line length (TLL), sample loading, and sodium chloride addition. Also, thermodynamics of partition process was addressed. Furthermore, systems top phase antioxidant activity and anti-proliferative properties against MCF-7 breast cancer cells were evaluated. A system with VR 3, TLL 40% w/w, 5 mg of crude extract/g of ATPS, and 3% w/w NaCl, showed the highest phenolic compounds recovery in the top phase (17.98%). Thermodynamic studies indicated that polarity governs the partition of phenolic compounds. The system with a VR 3, TLL 40% w/w, 5 mg of crude extract/g of ATPS, and without NaCl exhibited the highest antioxidant activity. HPLC analysis revealed no alteration on phenolic compounds profile after ATPS extraction. Whereas, the top phase of a system with VR 3, TLL 40% w/w, 5 mg of crude extract/g of ATPS, and 5% w/w of NaCl showed maximum inhibition of cell proliferation at 168 h (89.66%). The potential application of S. dendroideum as an anticancer agent is reported for the first time. ATPS could be used as an alternative extraction technique for further evaluation of phytochemical composition and pharmacological activities of phenolic compounds from S. dendroideum.