Journal of Supercritical Fluids, Vol.140, 137-146, 2018
Extraction of Arctium Lappa leaves using supercritical CO2 + ethanol: Kinetics, chemical composition, and bioactivity assessments
This study reports the extraction of Arctium lappa leaves using scCO(2) with ethanol as solvent (scCO(2) + EtOH) aiming the recovery of bioactive components. Experiments were performed varying the temperature (313.15-353.15 K), pressure (15-25 MPa), and ethanol to CO2 mass ratio in the static extraction step, where extraction yield, chemical composition, phenolic total content (TPC), antibacterial and antioxidant activity were determined. GC analysis showed diisooctyl phthalate, amyrin acetate, lupeol acetate and phytol as major compounds. It was observed the best relation between maximum yield (6.09%) and biological activities for the extract obtained at 353.15 K and 15 MPa. High values of antioxidant activity were found for the extracts obtained at 353.15 K and 15 MPa determined by the DPPH method and the phosphomolybdenum reduction method. The same extract presented the high phenolic content (35.51 mgGAE/gextract). High antibacterial activity was observed for all the extracts obtained with scCO(2) + EtOH against Staphylococcus aureus.