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

ABSTRACT

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.