Yerba Mate (Ilex paraguariensis) extraction using CO2 and hydrated ethanol as cosolvent

Abstract

Yerba mate is a plant that grows in subtropical South America that exhibit many healthbeneficial properties. In particular, the bio-extracts obtained from this plant findapplications in the manufacture of functional foods due to their stimulating andantioxidants properties. In this work, extract products were obtained from the extractionof yerba mate (Ilex paraguaryensis) by different high pressure technologies using liquidand supercritical CO2. Extractions were carried out in a high pressure Soxhlet apparatuswith liquid CO2 at 291 K and 55 bar. Also, supercritical CO2 extractions wereperformed at pressures between 175 bar and 260 bar and temperatures between 313 Kand 333 K. Yerba mate was previously impregnated with ethanol or an ethanolicsolution with 30 wt.% water (0.15 g/g to 1 g/g solution/yerba mate) to enhance theextraction of the main active principles. A wide range of global extraction yields(between 0.74 wt.% and 26.14 wt.%) were obtained in the experiments. Also,HPLC/MS-MS analyses of the extract products were performed to assess the selectivityof the different extraction conditions and cosolvents towards components like caffeine,theobromine, theophylline, caffeic acid and chlorogenic acid. Bioactive extractsobtained in this work show a high concentration of methylxanthines and chlorogenicacid, making these products valuable for functional food and nutraceutical applications.