Extraction of rosavin from Rhodiola rosea root using supercritical carbon dioxide with water

In this study, a new extraction method for the isolation of rosavin from dried crushed roots of Rhodiola rosea is being developed using supercritical CO2 and water. Rosavin extracts quantitatively and qualitatively were compared to commonly used solvents such as methanol, ethanol and ethyl acetate. By HPLC analysis rosavin was found to be the dominant compound in extracts obtained by both extraction methods. Quantitative differences were observed between the two extraction methods. Among the solvents, methanol yielded 3.3% while ethanol only 1.2% of rosavin. Supercritical CO2 and water at extraction temperature 80 degrees C and 5 h yielded 4.5% of rosavin. (C) 2009 Elsevier B.V. All rights reserved.