Extrakčné postupy pre izoláciu diterpénov z uhlia
The paper deals with the extraction of a tetracyclic diterpene from Slovak sub-bituminous coal. The extraction procedures used were Soxhlet, microwave-assisted, low-temperature supercritical fluid and high-temperature supercritical fluid (HSFE). The yield of the diterpene fraction containing 82.5 % of 16a(H)-phyllocladane was used to determine the efficiency of extraction procedures. HSFE seems to be the best though demanding procedure. The yield of the diterpene fraction obtained by Soxhlet and microwave-assisted extraction was 0.386 % and 0.254 %, respectively. Microwave-assisted extraction is much shorter compared with the other ones (min vs. days).