Optimization of Lactoperoxidase and Lactoferrin Separation on an Ion-Exchange Chromatography Step

Lactoperoxidase (LP), which is a high-value minor whey protein, has recently drawn extensive attention from research scientists and industry due to its multiplicity of function and potential therapeutic applications. In this study, the separation and optimization of two similar-sized proteins, LP and lactoferrin (LF) were investigated using strong cation exchange column chromatography. A two-step optimization strategy was developed for the separation of LP and LF. Optimization was started with central composite design-based experiments to characterize the influences of different decision variables, namely, flow rate, length of gradient, and final salt concentration in the linear elution gradient step on the yield of LP. This was followed by a more accurate optimization of ion-exchange chromatography (IEC) separation of LP and LF based on an experimentally verified chromatographic model. The optimal operating points were found and the results were compared with validation experiments. Predictions respecting yield confirmed a very good agreement with experimental results with improved product purity.