2.2. Isolation of the essential oils
Three replications of 100 g of air-dried and finely grounded
raw materials were submitted to hydrodistillation for 5 h with
500 mL distilled water using a Clevenger type apparatus
according to the European Pharmacopoeia (2004). The oil
obtained was collected and dried over anhydrous sodium sulfate
and stored in sealed glass vials in a refrigerator at 4 C
prior to analysis. Yield based on dry weight of the sample
was calculated (w/w%).