Extraction And Purification Of Salidroside

In this work, the following methods were used to obtain salidroside from Rhodiola sachalinensis:water extraction, ultrasonic extraction, microwave-assisted extraction, and the combination of supercritical CO2 extraction with one of the above three methods. The combination of supercritical CO2 and water gave the highest extraction percent of salidroside. The influence of solid-liquid ratio, extraction temperature, and extraction time on the yield of salidroside was investigated during water extraction. During microwave-assisted extraction, influence of the following factors on the extraction percent of salidroside was investigated:solid-liquid ratio, soak time, microwave power, microwave radiation time, and stirring time. For ultrasonic extraction, the factors investigated included solid-liquid ratio, soak time, ultrasonic power, ultrasonic time, and ultrasonic temperature. For the extraction with supercritical CO2 and water, factors including CO2 pressure, extraction temperature, extraction time, and extrainer concentration were optimized to be as follows:CO2 pressure 40 MPa, extraction temperature 55℃, extraction time 5 h, extrainer (absolute ethyl alcohol) 7 mL. The extraction percent of salidroside was 99.6%.Macroporous adsorption resins were applied to the isolation and purification of salidroside. The strong polar DA-201 was selected from 3 kinds of resin by comparing their physical properties and adsorption and desorption capacity for salidroside. Several factors including the amount of DA-201, the flow rate of adsorption, the concentration and amount of desorption reagent, and the flow rate of desorption were optimized. The optimum parameters were as follows:the amount of resin 5 mg salidroside/g dry resin, the flow rate of adsorption 1 BV/h, the desorption reagent 10% ethyl alcohol solution, the flow rate of desorption reagent 2 BV/h, the amount of desorption reagent 16 mL/g dry resin. Under these conditions, the purity of salidroside was>99%.