基于超滤-络合萃取及反萃取技术的甘草苷制备工艺研究

目的建立一种分离纯化甘草超滤液中甘草苷的络合萃取及反萃取制备技术。方法以甘草苷萃取率为指标,采用均匀设计确定最佳的络合萃取剂组成,再采用正交试验优选络合萃取工艺条件。以甘草苷反萃取率为指标,通过考察反萃取剂的种类及浓度,确定反萃取甘草苷的工艺条件。结果经络合萃取研究发现,络合萃取剂宜选用由三烷基氧化膦(TRPO)和磺化煤油组成的二元络合萃取剂。甘草苷的最佳络合萃取工艺条件为TRPO-磺化煤油(9∶91)、甘草超滤液pH值调至4、有机相与水相体积比为1∶1,甘草苷平均萃取率达到99.6%。反萃取工艺研究发现,在有机相与反萃取剂体积比为1∶1的条件下,17.5mmol/LNa OH水溶液为最佳反萃取剂,甘草苷的反萃取率为99.3%。结论在优选所得条件下,甘草超滤液中的甘草苷可实现从超滤液到络合萃取剂再到碱性反萃取剂的顺利转移,甘草苷总转移率高达98.9%,可为甘草苷的分离纯化提供一种全新的制备技术。

Preparation technology of liquiritin based on ultrafiltration-complexation extraction and back extraction technology

Objective To establish a complexation extraction and back extraction technology for the separation and purification of liquiritin from Glycyrrhiza uralensis ultrafiltrate. Methods Taking the extraction rate of liquiritin as an index, the optimum composition of complexing extractant was first determined by uniform design, and then orthogonal experiments were used to optimize the conditions of complexing extraction. Taking the back extraction rate of liquiritin as an index, the process conditions for the back extraction of liquiritin were determined by investigating the type and concentration of back extractant. Results The complexation extraction research found that the complexing extractant should be a binary complexing extractant composed of trialkyl phosphine oxide (TRPO) and sulfonated kerosene. The optimum extraction conditions for liquiritin were as follows:TRPO-sulfonated kerosene (9:91), pH value of G. uralensis ultrafiltrate was adjusted to 4, volume ratio of organic phase to aqueous phase was 1:1, and average extraction rate of liquiritin reached 99.6%. The study of back extraction process showed that under the condition that the volume ratio of organic phase to back extractant was 1:1, 17.5 mmol/L NaOH aqueous solution was the best back extractant, and the back extraction rate of liquiritin was 99.3%. Conclusion Under the optimized conditions, the liquiritin in G. uralensis ultrafiltrate can smoothly transfer from the ultrafiltrate to the complexing extractant and then to the alkaline back extractant. The total transfer rate of liquiritin is as high as 98.9%. This paper can provide a new preparation technology for the separation and purification of liquiritin.