Li Hui, Chen Bo, Zhang Zhaohui, Yao Shouzhuo
State Key Laboratory of Chemo/Biological Sensing & Chemometrics, Hunan University, Changsha 410082, PR China; College of Resources and Environmental Sciences, Jishou University, Hunan Jishou 416000, PR China.
Talanta. 2004 Jun 17;63(3):659-65. doi: 10.1016/j.talanta.2003.12.028.
A new focused microwave-assisted solvent extraction method using water as solvent has been developed for leaching geniposidic and chlorogenic acids from Eucommia ulmodies Oliv. The extraction procedures were optimized using a two indexes orthogonal experimental design and graphical analysis, by varying irradiation time, solvent volume, solvent composition and microwave power. The optimum extraction conditions were obtained: for geniposidic acid, 50% micorwave power, 40s irradiation, and 80% (v/v) aqueous methanol as extraction solvent (20mlg(-1) sample); and for chlorogenic acid, 50% micorwave power, 30s irradiation, and 20% aqueous methanol (20mlg(-1) sample). The composition of the extraction solvent was optimized and can be directly used as the mobile phase in the HPLC separation. Quantification of organic acids was done by HPLC at room temperature using Spherigel C(18) chromatographic column (250 mm x4.6 mm , i.d. 5mum), the methanol:water:acetic acid (20:80:1.0, v/v) mobile phase and UV detection at 240nm. The R.S.D. of the extraction process for geniposidic and chlorogenic acid were 3.8 and 4.1%, respectively.
已开发出一种以水为溶剂的新型聚焦微波辅助溶剂萃取方法，用于从杜仲中浸出京尼平苷和绿原酸。通过改变辐照时间、溶剂体积、溶剂组成和微波功率，采用双指标正交试验设计和图形分析对萃取过程进行了优化。获得了最佳萃取条件：对于京尼平苷，微波功率50%，辐照40s，80%（v/v）甲醇水溶液作为萃取溶剂（20mlg(-1)样品）；对于绿原酸，微波功率50%，辐照30s，20%甲醇水溶液（20mlg(-1)样品）。优化了萃取溶剂的组成，可直接用作HPLC分离中的流动相。在室温下，使用Spherigel C(18)色谱柱（250 mm×4.6 mm，内径5μm）、甲醇:水:乙酸（20:80:1.0，v/v）流动相和240nm紫外检测，通过HPLC对有机酸进行定量。京尼平苷和绿原酸萃取过程的相对标准偏差分别为3.8%和4.1%。
