Ultrasonic extraction
Extractions were carried out in an ultrasonic bath that
allows variation of amplitude and temperature. Working
frequency was set at 33 kHz. Four grams of material were
extracted with 100 ml 95% (v/v) ethanol in a conical flask
(100 ml) and kept for sonication for 15 min at room temperature.
After the extraction, the contents were filtered
and evaporated to dryness. The procedure of ultrasonic
extraction of material was repeated twice under the same
conditions.