Analysis of performance of the anion exchange and pseudo-affinity chromatography for intracellular enzyme purification

Development of a rapid and simplified primary capture step (i.e. fluidised/expanded bed adsorption) for the direct selective recovery of intracellular enzymes from particulate-containing yeast disruptate has been undertaken. The Kiesleguhr-agarose composite adsorbent derivatised with Cibacron Blue 3GA was used in batch binding experiments, as well as in commercial and custom assembled fluidised/expanded bed contactors. The results obtained were compared with the performance of the anion exchange adsorbent (Streamline QXL). The adsorbents were also subjected to hydrodynamic comparison experiments. The experimental values of the Richardson - Zaki coefficient determined here were close to the value of 4.8, commonly used in the laminar flow regime. The expansion coefficient and terminal velocity of the adsorbents were theoretically calculated from literature correlation and also measured experimentally herein. Use of the pseudo-affinity has enabled the enzyme to be more selectively captured, indicating that there was less interference of negatively charged components present in the feedstock. Additionally, the better adsorption performance achieved in this study attributed to the fact that dye-ligand was less sensitive to the ionic strength of feedstocks. The generic application of such techniques for the recovery of intracellular products is discussed.