Aqueous Two-Phase Extraction for the Recovery of Beet Pigments and Enzymes

Abstract

Liquid–liquid extraction employing aqueous two-phase systems has proved to be a promising separation strategy for many biological products such as proteins, enzymes, viruses, cells and other biological materials. The major advantages of aqueous two-phase extraction (ATPE) include high capacity, biocompatible environment, low interfacial tension, high yield, lower process time and energy and high selectivity. ATPE can be designed such that the desired biomolecule selectively partitions to one of the phases in a concentrated form, with considerable reduction in the volume of the stream to be handled during the subsequent purification steps. Therefore, it is relatively easier to scale up partitioning steps with greater precision in enzyme/protein isolation and purification when compared with conventional steps. Recovery of natural color pigments (betalains) and enzymes (peroxidases, polyphenol oxidases) from beet root are presented in this chapter, bringing out the versatility of ATPE for their purification and concentration.