(1) Background: Aqueous two-phase systems (ATPSs) have been widely used in the separation and purification of bioactive substances in recent years. (2) Methods: In this study, deep eutectic solvents (DESs)-based ATPSs were employed for the extraction and separation ofAstragalus membranaceuspolysaccharides (AMP). The optimal DES (choline chloride:urea = 1:1) was first screened to extract AMP, and the effect of DES concentration, solid–liquid ratio, pH, extraction temperature, and extraction time on the extraction yield of AMP were investigated. (3) Results: The maximum extraction yield was 141.11 mg/g under the optimum conditions. AMP was then preliminarily purified by ATPS, to further realize the recycling and reuse of DES. The effect of type of salts, salt concentration, and extraction temperature on extraction efficiency was investigated. The extraction efficiency was 97.85% for AMP under the optimum ATPS conditions. Finally, the obtained AMP was studied by molecular weight determination, infrared spectroscopy analysis, and monosaccharide composition analysis. (4) Conclusions: This ATPS extraction based on DESs is simple, environmentally friendly, low-cost, and has high extraction efficiency, which provides new ideas for the extraction of plant polysaccharides and other bioactive compounds.Keywords:Astragalus membranaceuspolysaccharides;deep eutectic solvents;solid–liquid extraction;aqueous two-phase system;separation and purification
Wang Wenchao,An Lianhao,Lei Junrong,Li Dan,Shen Zheluan,Wang Hong,Li Qingyong
Pearl powder has been used in medicine and beauty treatment since ancient times in China. However, it is still unclear whether the biological activities of pearl powder are affected by different extraction methods or not. In this study, we determine the total protein yield, protein molecular weight and biological activities including antioxidant, tyrosinase inhibition and melanogenesis inhibition activities and cytotoxicity of different pearl powder extracts prepared by five different preparation methods. The ultrasonic-assisted extraction (UAE) and microwave-assisted extraction (MAE) of pearl powder were optimized by the response surface method based on total protein yield. Compared with solid-liquid extraction (SLE), the optimized UAE and MAE increased the total protein yield without changing protein molecular weight. In addition, the extract by MAE enhanced the tyrosinase inhibition activity and anti-melanogenesis activity slightly. Acidolysis hydrolyzes macromolecular protein into small molecules with obvious cytotoxicity and low activities. Enzymolysis can hydrolyze macromolecular protein into small molecules with high protein yield and improvement of bioactivities. In the determination of the antioxidant assay, the extract prepared by the enzymolysis showed significant activity. These results suggest that protein molecules of the pearl powder extract are degraded appropriately by enzymolysis to smaller molecules to obtain the enhanced biological activities that can be applied in the cosmetic industry.