Extraction by Microwave-assisted Steam Distillation and GC-MS Analysis of Volatile Oil from Artemisia rubripes Nakai

OBJECTIVE The method of extraction of volatile oil from Artemisia rubripes Nakai by microwave-assisted steam distillation(MAE-SD) was developed in this work. METHODS The extraction conditions were optimized by single factor firstly and then orthogonal array design methods. And the chemical compositions of samples were analyzed by gas chromatography-mass spectrometry(GC-MS). RESULTS The optimal extraction conditions of MAE-SD were: microwave power at 480 W, solid/liquid ratio at 1:10 g.mL-1, and water-soaked time for 4 h. Under this condition, the yield of volatile oil obtained by MAE-SD was 0.29% with extraction time of 29 min, which was obviously higher than that of 0.23% obtained by steam distillation (SD) for 3 h. Sixty-one compounds had been identified by GC-MS. The main components of volatile oil were caryophyllene(13.85%), alcanfor(11.51%), cineole(9.84%), caryophyllene oxide(4.80%), germacrene D(3.99%), ?-selinene(3.47%), 1-terpinen-4-ol(2.50%), eudesm-7(11)-en-4-ol(2.50%). Compared with SD, the main constituents and the relative contents of volatile oil were basically similar, but there were also some differences between them. CONCLUSION MAE-SD had the advantage of efficiency, and it was suitable for the extraction of volatile oil from Artemisia rubripes Nakai.