中文摘要：

以中药薤白为原料,对薤白进行加温浸泡、超声预处理后,采用水蒸气蒸馏法提取薤白中挥发油.以挥发油提取率为考察指标,在单因素试验的基础上,采用响应面法优化提取工艺条件,并利用气相色谱-质谱法对挥发油化学成分进行分析.结果表明：最佳工艺条件为浸泡温度40℃、超声预处理30 min、液固比4.40：1（mL/g）、蒸馏时间2.2 h,此条件下薤白挥发油提取率达1.030％.经气相色谱-质谱分析,共测出其中17个组分.采用峰面积归一化法测定各组分的相对含量,其中已鉴定出的14种化合物组分占提取物的93.46％.

英文摘要：

The volatile oil from the bulbs ofAllium macrostemon Bunge was extracted by steam distillation with soaking in hot water and ultrasonic pretreatment.Based on single factor experiments,the yield of volatile oil was selected as response value and the optimum extraction process was determined through response surface methodology.The chemical constituents of the volatile oil were analyzed by gas chromatography mass spectrometry （GC-MS）.The results showed that the optimal extraction conditions were soaking in 40 ℃ water with a liquid-to-solid ratio of 4.40∶1 （mL/g）,ultrasonic pretreatment for 30 min and distillation for 2.2 h.Under these conditions,the yield of volatile oil was 1.030％.Totally 17 compounds were detected and 14 of them were identified by GC-MS in the extracted volatile oil,together accounting for 93.46％ of the total amount of extracted compounds based on peak area normalization.