Antioxidant activity and fatty acid profile of yacon leaves extracts obtained by supercritical CO2 + ethanol solvent

Abstract Extraction efficiency of bioactive compounds from yacon leaves using supercritical CO 2 + ethanol (scCO 2 +EtOH) fluid extraction and a conventional method were investigated. scCO 2 +EtOH runs were performed under the following conditions: 30–70 °C, 15–25 MPa and varying the ethanol (co-solvent) to solid (raw material) mass ratio (MR). All extractions were evaluated in terms of overall extraction yield (X 0 ), fatty acid composition, total phenolic content (TPC) and antioxidant activity (AA). Results indicated that scCO 2 +EtOH presented the highest extraction yield 5.22 wt% at 70 °C/25 MPa/MR 3:1. High values of TPC and AA were found in all extracts. Major unsaturated fatty acids found in yacon leaves extracts were gamma-linolenic (ω-6), eicosapentaenoic (ω-3) and linoleic (ω-6) acids. The highest ω-6/ω-3 fatty acids ratios were found in the extracts obtained using scCO 2 +EtOH.