Martin Topiar
University of Chemistry and Technology Prague, Czech Republic
Title: Supercritical CO 2 in its multiple roles: solvent for fractionation of complex mixtures and blowing agent in polymer foaming
Biography
Biography: Martin Topiar
Abstract
Carbon dioxide in its supercritical state (sc-CO2) can find application in formation of microcellular polystyrene foams (PSF) with improved thermal properties in comparison with PSF on the market. A most important application of sc-CO2 on industrial scale is supercritical fluid extraction (SFE) from plants. Both processes have been studied in our laboratory. Although the SFE is more selective than common extraction methods, CO2 extracts still contain a mixture of chemical compounds. If a high concentrated isolate is required, suitable fractionation methods have to be involved into the process. Supercritical adsorption, a novel promising method combining SFE from plants with selective adsorption of extracted compounds, could be a solution when high purity isolates free of any traces of organic solvents are required. We used this method for fractionation of turmeric (Curcuma longa L.) isolate obtained by SFE. The major compounds analyzed by GC were turmerone (22.7 wt.%), ar-turmerone (13.2 wt.%) and curlone (13.8 wt%). Turmerones belong to widely studied substances with potential use in the treatment of neurodegenerative diseases. The efficiency of fractionation was studied in terms of adsorption conditions, adsorbent type and sorbent-to-feed ratio. The concentration of turmerones in isolate increased from the initial 49.7 wt.% up to 93.8 wt% with using a particular type of silica gel. Moreover, the concentration of β-sesquiphellandrene, a compound with a potential anticancer activity, in volatile fraction obtained from supercritical adsorption process was almost 16 times higher than in the initial sample. These are promising results for a more detailed subsequent research on this method.