Applications of Rotation Locular Countercurrent Chromatography in Natural Products Isolation

Abstract
Purification of natural products and the fractionation of crude plant extracts are processes which traditionally involve adsorption and/or molecular exclusion chromatography. While countercurrent chromatography avoids the irreversible adsorption and decomposition frequently encountered in absorption chromatography, the classical countercurrent distribution technique is both time- and solvent-consuming, consequently it is of limited value today. Rotation locular countercurrent chromatography (RLCC) is one of 3 new countercurrent techniques, the others being droplet countercurrent chromatography and planet coil countercurrent chromatography, which have revived the chromatographic application of liquid-liquid partition. A commercially available RLCC apparatus was used in the isolation of several natural products [flavonoid aglycones, Swertia perennis constituents, Streptomyces griseus chromomycins, Daucus carota growth regulator] with a broad range of polarity, demonstrating the versatility of the RLCC with regard to the functionality of the compounds to be isolated.