Extraction of bio-active components from Rhodiola sachalinensis under ultrahigh hydrostatic pressure

A new extraction technique, ultrahigh hydrostatic pressure (UHP), was used to obtain bio-active components from Rhodiola sachalinensis. The leaching-out rates of flavones and salidroside were measured under different conditions. The extraction efficiency of different extraction methods and the DPPH radical scavenging activities of their crude extracts were investigated. The optimal conditions of extracting flavones and salidroside were as follows: 41 or 60% (v/v) of ethanol concentration, 70:1 ml/g of solvent–herb ratio, and 500 MPa of hydrostatic pressure for 3 min. The leaching-out rate of flavones and salidroside was up to 5.233 and 0.411%, respectively. The yield of crude extract of UHP was up to 26.116%, comparing with the crude extract was 13.825% by reflux and 16.995% by soxhlet. The UHP extraction technique showed high efficiency in extracting bio-active components at room temperature. The crude extract had stronger DPPH radical scavenging activity than TBHQ.