Comparative study on optimization of continuous countercurrent extraction for licorice roots

Abstract

Traditional methods for extraction of botanicals, namely maceration and percolation, are typically batch processes with limited scalability. Continuous countercurrent extraction using horizontal screw to convey feed material against the percolating solvent is not only a high throughput process but also a system with good scalability. It well features an ideal countercurrent mode and intimate solid-liquid contact for high recovery of solids with minimum solvent consumption. In this study, the applicability of a pilot scale horizontal screw continuous countercurrent extractor for the extraction of glycyrrhizic acid from licorice roots was demonstrated. The study has provided a better understanding of the operation of the system and the impact of the various process and feed variables on its extraction efficiency. Operated under optimum conditions, it is more efficient than maceration for the extraction of licorice roots. The extraction process can be easily optimized and is potentially useful for the extraction of bioactive principles from botanicals of medicinal value.