甘草中甘草酸的微波萃取

Microwave extraction of glycyrrhizic acid from Glycyrrhiza uralensis

目的 研究利用微波萃取技术提取甘草中甘草酸的方法。方法 采用正交试验考察提取温度、提取时间、微波功率对甘草酸含量和提取总时间的影响 ,确定微波萃取甘草中甘草酸的最佳工艺条件。在优选出的微波萃取最佳工艺条件下 ,考察了提取溶剂对甘草酸含量的影响 ,并与超声波提取法、室温冷浸法和索氏提取法比较。结果微波提取的最佳条件为以 0 5 %氨水为提取溶媒 ,微波功率为 2 0 0 0W ,体系温度升至 6 0℃后保温提取 4 0min。微波萃取 5 4min与索氏提取 4h、室温冷浸 4 4 3h的甘草酸得率相当。结论 微波萃取具有快速、高效、节能、选择性好的特点 ,可用于中草药有效成分的提取 ,值得推广应用。

Object A novel microwave-heated extraction (MHE) method was studied for the extraction of glycyrrhizic acid from Glycyrrhiza uralensis Fisch. Methods Several factors, such as temperature, time and microwave power were investigated and the appropriate MHE conditions were obtained from the orthogonal test. Under the optimum conditions, the optimal solvent was selected and the MHE was compared with ultrasonic extraction, leaching at room temperature and Soxhlet extraction,. Results The optimum conditions of MHE is extracting for another 40 min in 0.5% ammonia water after heated to 60 ℃ by microwave of 2 000 W. Yield of glycyrrhizic acid was about equal to that of Soxhlet extraction for 4 h, and that of leaching at room temperature for 44.3 h. Conclusion The MHE method is fast, efficient, energy-saving and high-selective, which is recommendable to the application to active compounds extraction from Chinese herbal medicines.