无溶剂微波提取-气相色谱-质谱法测定八角挥发油

GC-MS Determination of Essential Oil in Anise with Solvent-free Microwave Assisted Extraction

将干八角粉碎至过2.00mm孔径的药筛,取20g样品间歇性喷雾加水至其含水量(质量分数)达50%,置于圆底烧瓶中,用LWMC-204微波化学反应器在180W微波功率进行无溶剂微波辅助提取(SFME),所得提取液用无水硫酸钠干燥置于4℃保存。此溶液用于气相色谱-质谱法测定其中的挥发油组分,将所得结果与SFME法和水蒸气蒸馏法(SD)所得数据对比,可知SFME法提取挥发油有以下特点:①该法仅需30min提取即可达到其最高提取率7.71%;②经此法分离后在挥发油中共测得25种化合物,达总量为98.94%;③所测得的含氧单萜类化合物高于SD法提取所得;④所测得挥发油的主要成分反式茴香脑的含量较SD法提取所得的量高1.4倍。

20 g of sample of dried anise （crushed to pass 2. 00 mm sieve） in a round-bottom flask was sprayed with water intermitently until its moisture content attained to 50%, and then treated with solvent-free microwave assisted extraction （SFME） in LWMC-204 Microwave Chemical Reactor at 180 W. The extract was dehydrated with anhydrous Na2 SO4 and stored at 4 ℃, and was used for GC-MS analysis for composition of the essential oil. As shown by the analytical results and the comparative study between the data obtained by the methods of solvent-free microwave assisted extraction （SFME） and steam-distillation （SD）, the following specific features were found with the SFME method： （1） only 30 rain were required to attain to the max. extraction rate of 7.71%; （2） 25 compounds were found amounting totally to 98. 94 % （relative content） ; （3） more oxygen-containing monoterpenes were found as compared with the SD method; （4） main component of the essential oil was found to be trans-anisole which was the same compound found by SD, but the relative content （%） found by SFME was 1. 4 times higher that found by SD.