Effects of Entrainer on Astragaloside Extraction from Astragalus by Supercritical CO2 / 中国药师

ABSTRACT

Objective:To research the effects of entrainer on extracting astragaloside from astragalus by supercritical CO2 . Meth-odsThe optimum extraction technology conditions were investigated by an L9 (34 ) orthogonal experiment with the extraction rate of as-tragaloside as the evaluation index and the addition way, variety, amount and flow rate of the entrainers as the investigation factors. The content of astragaloside was determined by HPLC. Results:The addition way of entrainer was the presoak treatment combined with the dynamic extraction mode, and the entrainer was 95 % alcohol with 300 ml of infusing volume and 10 ml·min-1 flowing volume. The best factors of supercritical fluid extraction were as followsthe extraction pressure was 35 MPa, the extraction temperature was 45℃, the outlet temperature was 55℃, the extracts were collected with 95% alcohol, and dynamic extraction time was 2 h. Under the above process conditions, the extraction rate of astragaloside was 0. 040 7%. Conclusion:The extraction of astragaloside from astragalus by supercritical CO2 extraction with the optimized process is significantly improved.