Ultrasonic and microwave-assisted steam distillation (UMASD), microwave-assisted steam distillation(MASD) and steam distillation(SD) were used to extract essential oil from dried Litsea cubeba fruits. The extraction process was optimized by single factor experiments. The extraction yield of UMASD was 3.22% under the optimum conditions of microwave power 100W, liquid to solid ratio 20 : I and extraction time 2 hours. The extraction yield of MASD was 3.20% under the optimum conditions of microwave power 100 W, liquid to solid ratio 20 : 1...