Ecological plant extracts, that are rich in biologically active substances, are a valuable raw material for the food industry, thus new sources thereof are constantly searched for. Special attention is paid to common plants that are resistant to difficult weather conditions, easily available and inexpensive to grow. This type of plants includes stinging nettle (Urtica dioica L.). The objective of the research study was to determine the profile of fatty acids contained in stinging nettle leaves, in extracts obtained by an extraction method using supercritical carbon dioxide with the addition of ethanol. There were obtained 5 extracts that differed in the method of obtaining them and in the process parameters – time, pressure and temperature. A GC-MS method was applied to determine the fatty acid profile. To identify the compounds, mass spectra were compared with the NIST 11 library as were retention times with a certified reference material. In all the extracts the content of unsaturated fatty acids was higher than that of saturated fatty acids. The research study showed that the increase in temperature and pressure resulted in washing out a greater amount of desirable unsaturated fatty acids. The highest content of unsaturated fatty acids was reported in the extract obtained at a temperature of 50 ºC and a pressure of 250 bars. In the extracts obtained using a low pressure and an extended extraction time was not identified eicosapentaenoic acid, which was present in the remaining samples.
stinging nettle, supercritical carbon dioxide extraction, gas chromatography, profile of fatty acids