摘要
利用超临界二氧化碳对秋水仙块根（经粉碎）中的秋水仙碱进行了萃取，采用高效液相色谱法对萃取出的秋水仙碱的质量分数进行了测定。实验选择40℃20～40MPa作为超临界苹取的操作条件，采用体积分数为95％的乙醇在索氏提取器中对样品进行了对比苹取实验。结果表明:不加浸泡剂进行浸泡处理的样品中的秋水仙碱很难被超临界二氧化碳萃取，在40℃，35MPa条件下，消耗1．28mol的二氧化碳只得到3％的萃取率。加入极少量的有机溶剂浸泡处理样品15min后再进行超临界萃取，可以极大程度地提高秋水仙碱的萃取率。在所选的浸泡剂乙醚、丙酮、乙腈、甲醇、乙醇中，乙醇浸泡效果最佳，经浸泡后，在40℃，35MPa条件下进行超临界二氧化碳萃取，仅消耗0．21mol的二氧化碳，一次苹取的秋水仙碱萃取率就达80％。秋水仙碱的质量分数从原植物样品中的0．18％提高到萃取物中的6．92％，提高了近38倍，而有机溶剂乙醇提取只能达到0．98％，仅提高了5倍。超临界苹取后的样品经简单的过滤即可进样进行HPLC分析，有机溶剂乙醇提取则需要氯仿苹取、溶剂回收等样品制备过程。HPLC分离测定秋水仙碱采用苯基柱，甲醇-水梯度洗脱，流速0．5mL／min，UV检测λ=353um，经选择，其最佳条件为：从V（甲醇）：V（水）=50：50开始。
Colchicine was successfully extracted from the corms of colchicine autumnele Liliaceae using supercritical fluid (SF) CO_2. The pressure range used in the experiments was 20--40 MPa and the temperature was 40 C. Being its high molecular polar, colchicine or other alkaloids are not easy to be extracted by SF CO_2. In order to increase the mass transfer from the sample matrix to SF, different presoakers (such as methanol, ethanol,acetone etc. ) were employed. Among the selected pre-soakers, best results were obtained with ethanol both in the aspects of yield and selectivity. At 35 MPa, 40 ℃ and with ethanol as pre-soaker, the yield was 1. 8 mg/g,and the colchicine could be almost completely extracted from the sample matrix. The average concentration increased from 0. 18% in natural sample to 6. 92% in extract with SFE processing only once under the given conditions. The comparison of liquid ethanol extraction (LEE) and SFE showed that SFE is greatly superior to LEE in colchicine separation with SFE not only higher yield and selectivity but also a quick, safe and non-toxic method were obtained in colchicine extraction.
出处
《色谱》
CAS
CSCD
北大核心
1999年第3期249-252,共4页
Chinese Journal of Chromatography
基金
云南省科委基础研究基金
关键词
高效液相色谱
超临界
萃取
秋水仙碱
测定
high performance liquid chromatography, supercritical fluid extraction, colchicine
