Acta Pharm. 51 (2001) 45-51

Original scientific paper  
 

Contents of fatty acids in stinging nettle extracts (Urtica dioica L.) obtained by supercritical carbon dioxide

VESNA RAFAJLOVSKA,1* VESNA RIZOVA,2 ZOLTAN DJARMATI,3
VERONA TESEVIC3 and  LJUBOMIR CVETKOV1

1Faculty of Technology and Metallurgy, Skopje, Republic of Macedonia
2Republic Institute of Health Protection, Skopje, Republic of Macedonia
3Technical-Ecological Center, Zrenjanin, SR Yugoslavia
Received June 7, 2000      Accepted February 9, 2001

In the stinging nettle leaf extracts, obtained with CO2 at supercritical conditions, the presence and contents of fatty acids, palmitic (C16:0), stearic (C18:0), oleic (C18:1), linoleic (C18:2) and linolenic (C18:3), were evaluated. Methyl esters of the fatty acids prepared with methanolic solution of sulphuric acid were determined by gas chromatography. Saturated fatty acids showed better solubility in supercritical CO2 at a lower pressure and temperature. The highest content of total fatty acids of 44.1% was found in the stinging nettle leaf extracts obtained at 140 bar, 333 K, after 6 h of extraction and 8.3% content of moisture in the raw material. As much as 6.8, 1.1, 3.6, 20.2 and 12.4% of C16:0, C18:0, C18:1, C18:2 and C18:3, respectively, was found.


Keywords: stinging nettle, Urtica dioica L., fatty acids, supercritical extraction