Enhanced Extraction of Bioactive Components of 3,29–Dibenzoylkarounidiol and Polysaccharides from Semen richonsanthis Using Subcritical Water Technology.

The efficient and green extraction of oil– and water–soluble essences from natural products is a key step in producing bioactive compounds and value–added chemicals. Herein, two components with different polarities from Semen richonsanthis were extracted using static subcritical water extraction technology at different temperatures (80–160°C), extraction times (5.0–30.0 min), and water loadings (2.0–6.0 mL). The oil–soluble and water–soluble components were measured by HPLC and phenol–sulfuric acid method, respectively. The optimum conditions of 3,29–dibenzoylkarounidiol (0.102±0.004%) and polysaccharides (0.462 ±0.021%) were obtained at 130°C, 10 min and 4.0 mL water loading. Compared with ultrasonic and heating reflux extraction, the three extracts were assessed by antioxidant activity against 2,2–diphenyl–1–picrylhydrazyl and the cytotoxicity towards HeLa cells. Overall results showed that the activities of subcritical water extracts are more promising than the other extracts and can be safely applied to pharmaceutical and nutraceutical products. Lastly, the morphological changes were evaluated by SEM which indicated subcritical water have a destructive effect on the cell wall. [ABSTRACT FROM AUTHOR]