Influence of Drying Time and Process on Artemisia herba-alba Asso Essential Oil Yield and Composition

The essential oil content of Artemisia herba-alba Asso decreased along the drying period from 2.5 % to 1.8 %. Conversely, the composition of the essential oil was not qualitatively affected by the drying process. The same principle components were found in all essential analyzed such as alpha-thujone (13.0 - 22.7 %), beta-thujone (18.0 - 25.0 %), camphor (8.6 - 13 %), 1,8-cineole (7.1 - 9.4 %), chrysanthenone (6.7 - 10.9 %), terpinen-4-ol (3.4 - 4.7 %). Quantitatively, during the air-drying process, the content of some components decreased slightly such as a-thujone (from 22.7 to 15.9 %) and 1,8-cineole (from 9.4 to 7.1 %), while the amount of other compounds increased such as chrysanthenone (from 6.7 to 10.9 %), borneol (from 0.8 to 1.5 %), germacrene-D (from 1.0 to 2.4 %) and spathulenol (from 0.8 to 1.5 %). The chemical composition of the oil was more affected by oven-drying the plant material at 35 degrees C. alpha-Thujone and beta-thujone decreased to 13.0 % and 18.0 % respectively, while the percentage of camphor, germacrene-D and spathulenol increased to 13.0 %, 5.5 % and 3.7 %, respectively.