中文摘要：

目的研究适于液相色谱-电喷雾串联质谱法（LC-MS/MS）定量测定富硒葱蒜类植物中Se-甲基-硒半胱氨酸（MSeC）的提取液的最佳制备条件。方法用4种提取剂（纯水、甲醇、丙酮和乙酸乙酯）、2种提取方法（超声提取和沸水提取）、不同水提取温度（70、80、90和100℃）和时间（45、60、75和90min）对富硒大蒜中的MSeC的最佳提取条件依次筛选研究,获得满足最大量测得MSeC的样品制备方法。按照选择条件提取洋葱、韭葱和大葱加标粉制剂,并采用LC-MS/MS测定MSeC含量,计算加标回收率。结果4种提取剂的超声提取对比分析发现,纯水提取蒜粉中MSeC的量最大,沸水浴加热比单独超声处理能够提高蒜粉中MSeC的提取率。水加热提取温度和时间二因素正交设计优选实验证实,蒜粉中MSeC最佳提取制备条件为100℃提取90min,该提取条件处理其他葱蒜类粉制剂的MSeC加标回收率在91%～108%之间。结论沸水提取90min适用于LC-MS/MS在线定量分析葱蒜类植物中MSeC的待测液的制备。

英文摘要：

Objective To obtain optimal extracting conditions suitable for the quantitative assay of MSeC in Se-enriched Aliium vegetables with on-line high-performance liquid chromatography-electron spray tandam mass spectrometry （LC-MS/MS）.Method Four kinds of extractant （methanol,deionized water,acetone and acetic ether）,two extraction methods （ultrasonic wave extraction and boiling water leach）,as well as different temperature （70,80,90 and 100 ℃） and different extracting time （45,60,75 and 90 min） for deionized water were investigated. The optimal extracting conditions were selected according to the maximum peak area of MSeC in LC-MS/MS chromatograms and verified by spiking recovery on three Allium vegetables （onion, leek and green Chinese onion）. Results The comparative analysis on the extraction of four types of extraetant with ultrasonic wave showed that the extraction rate of MSeC from Se-enriched garlic powder with deionized water was the highest among the four types of extractant. The extraction with boiling water was better than that with ultrasonic wave only, with a spiking recovery of 68.1% and 49.2 %, respectively. The optimal condition determined by orthogonal experimental design for temperature and time for the extraction with deionized water was leaching in 100 ℃ water for 90 minutes. The spiking recovery of MSeC varied from 91% to 108% for the three Aliium vegetables. Conclusion Leaching in boiling water for 90 minutes is suitable for the preparation of Aliium vegetable extracts to quantify the MSeC with on-line LC-MS/MS.