Abstract: In order to establish an optimal process for the extraction of total triterpenoids from Poria cocos peel by supercritical CO2 extraction, the effects of different factors including entrainment agent dosage, extraction pressure, extraction temperature and extraction time on extraction efficiency were explored. The optimal extraction process parameters were entrainment agent dosage of 2.0 mL/g, extraction pressure of 35 MPa, extraction temperature of 65 ℃ and extraction time of 60 min. The extraction efficiency of supercritical CO2 extraction for total triterpenoids was 2.06%, while the extraction efficiency of traditional enthanol extraction was 1.39%. Therefore, supercritical CO2 extraction is a stable, reliable, convenient and practical method for the extraction of total triterpenoids from Poria cocos peel.

Key words: Poria cocos peel, total triterpenoids, extraction, supercritical CO2