PLE procedure was optimized. And the parameters
include the type of solvent (methanol, ethanol, ethyl acetate
and petroleum ether), particle size (0.15–1.99 mm), temperature (80–160 ◦C) and static extraction time (5–15 min) were
studied by using univariate approach. Total amount of 11
investigated compounds were used as the markers for evaluation of extraction efficiency. The recovery efficiency for the
PLE procedure was determined by performing consecutive
pressurized liquid extractions on the same sample under the
optimized PLE conditions, until no investigated compounds