Countercurrent Separations as Effective Purification Techniques for Iridoids

Countercurrent separation (CCS) is a powerful technique for natural products purification in which the components of the sample are partitioned between two immiscible liquids. Iridoids are natural compounds with remarkable biological and pharmacological activities that have been purified by CCS, with high potential to be scaled up. This review provides CCS fundamentals, a critical consideration of existing studies focused on iridoid purification, and elucidating factors that can improve the processing, such as solvent system selection, processing parameters, and sample pretreatment, which are highly relevant for separation. This review highlights the use of CCS in the purification of iridoids, providing fundamental insights to better understand the CCS technique's contribution to purification improvement. By identifying the process key parameters and addressing issues, the implementation on an industrial scale of CCS for iridoid recovery could be facilitated, with high potential in the food, pharmaceutical, and cosmetic fields.