Supercritical CO2 extraction of resveratrol and its glycoside piceid from Chinese traditional medicinal herb Polygonum cuspidatum

Abstract

AbstractResveratrol (3,5,4′‐trihydroxystilbene) and its glycoside piceid are phenolic compounds found to be beneficial to health. In this paper, resveratrol and piceid were successfully extracted from the Chinese traditional medicinal herb Polygonum cuspidatum (Hu Zhang in Chinese), with supercritical CO2 plus ethanol modifier. The effects of ethanol content, pressure and temperature on the yields of resveratrol and piceid were investigated. Results showed that the extraction pressure was the main factor for the effective extraction of the two substances in the presence of ethanol modifier, especially for piceid. The optimal extraction condition was obtained: 30 MPa, 50 °C, (100 ml l−1), ethanol and 20 kg h−1 of CO2, at which the yields of resveratrol and piceid were 7.1 g kg−1 and 16.0 g kg−1, respectively. The yields obtained by supercritical fluid extraction (SFE) was comparable with those obtained by traditional organic solvent methods, indicating that SFE is an alternative method for extraction of the two compounds. Copyright © 2004 Society of Chemical Industry