Extraction of Resveratrol and Emondin from Polygonum cuspidatum by Supercritical CO_2 with Different Solubilizers

Objective To explore the effect of different solubilizers,pressure and extract time in the extraction of resveratrol and emondin by supercritical CO 2( SCE). Methods Resveratrol and emondin were extracted from Polygonum cuspidatum by SCE with different solubilizers,including AOT,PVP k-90,Poloxamer 188,and Tween 80. The parameters of SCE such as concentration of solubilizer,pressure,and extraction times were optimized. The extraction results were compared with heat reflux extraction. Results: The results show that resveratrol was hardly extracted by SCE with ethanol as modifier( the yield was 0. 015 mg/g),but AOT could enhance the extraction yield of resveratrol significantly( the yield was 0. 304 mg / g),while the yield of emodin was influenced gently by using these solubilizers. The yield of emodin was highest( 1. 008 mg / g) when PVP was used as modifier,but when the Tween 80 was used the yield was the lowest( 0. 679 mg / g). The optimal process was as follow: pressure at 25 MPa,temperature at 50 ℃,the concentration of AOT was 0. 05 mol / L and extracted for 3 times. Under this condition the yield of resveratrol was 0. 31 mg / g which was dropped by 81. 5% than extracted by heat reflux extraction. The yield of emondin was 0. 97 mg / g which was increased by 86. 5% than extracted by heat reflux extraction. Conclusion: The yields of resveratrol and emondin extraction from Polygonum cuspidatum by SCE can be improved by introducing AOT,PVP k-90 and Poloxamer 188 into supercritical CO 2. Based on the comparison of SCE and heat reflux extraction,the advantage of SCE is less extraction time at lower operating temperature without using large amount of organic solvent.