Continuous flow aqueous two-phase extraction of betalains in millifluidic channel

Aqueous Two-Phase System (ATPS) has a proven ability for the selective partitioning and purification of bioactives. This work explores the application of ATPS for the continuous flow extraction of bio-active solute (betalains) from an actual crude extract i.e. red beetroot extract. ATPS composed of Polyethylene Glycol (PEG) 6000 and ammonium sulphate is used for the differential partitioning of betalains and sugars. The continuous flow experiments were performed in millichannel (ID = 1.2 mm) with T-junction. The effect of residence time, multiphase hydrodynamics, and flow-rate ratios on the extraction performance in the continuous flow is studied. The effectiveness of the continuous flow extraction is compared with batch mode extraction of betalains. The continuous flow extraction offers 72.01 % extraction and 89.27 % equilibrium extraction efficiency for betalains with a residence time of 3.38 min. In comparison, batch extraction offered lower performance, with 60.35 % extraction and 74.81 % equilibrium extraction efficiency in 5 min. The improved performance for the continuous flow extraction is attributed to the uniform slug flow in the millichannel. Inclusively, this work develops a continuous flow process for the intensification of extraction of bioactives from the crude extracts of natural sources.