Study On Aqueous Two-phase Extraction Of Salidroside

In this study, a crude extract of salidroside was obtained by extracting the salidroside from Rhodiola root through reflux extraction technology. Salidroside was separated and purified by using the aqueous two-phase extraction technology in this experiment.The behaviors of form two-phase and two-phase partitioning were discussed in the polyethylene glycol (PEG)/salt aqueous two-phase systems (ATPS), and PEG/(NH4) 2SO4 aqueous two-phase system was the optimal aqueous two-phase system, so the PEG/(NH4)2SO4 aqueous two-phase system was choosed to separate and purify Salidroside. In this paper, each single factor of aqueous two-phase system was discussed, such as the effections of polyethylene glycol molecular weight, the type of salt, mass fraction of salt, ion concentration, extraction temperature and time, and the initial concentration of Salidroside on extraction of salidroside were studied. At last the optimum process conditions to separate and purify the Salidroside were obtained:When PEG1000 mass fraction is 24%, ammonium sulfate mass fraction is 16%, KCl as the extra add salt and mass fraction is 1%, extraction temperature is 25℃, extraction time is 120min, and the initial concentration of salidroside was 0.14mg/mL, the best extraction rate can be achieved, and the extraction rate of salidroside is 95.56%.The mechanism of aqueous two-phase extraction system was discussed.