Biotechnology and Bioengineering, Vol.80, No.2, 201-212, 2002
Operational intensification by direct product sequestration from cell disruptates - Application of a pellicular adsorbent in a mechanically integrated disruption-fluidised bed adsorption process
A novel prototype adsorbent, designed for intensified fluidised bed adsorption processes, was assembled by the emulsification coating of 4% (w/v) porous agarose upon a zirconia-silica solid core. The adsorbent, designated ZSA (particle density 1.75 g/ml, maximum pellicle depth 40 mum), was subjected to physical and biochemical comparison with the performance of two commercial adsorbents (Streamline and Macrosorb K4AX). Bed expansion qualities and hydrodynamic characteristics (N, D-axl, and B-o) of ZSA demonstrated a marked robustness in the face of elevated velocities (up to 550 cm/h) and biomass loading (up to 30% (ww/v)) disrupted yeast cells. Cibracron Blue derivatives of the pellicular prototype (ZSA-CB), evaluated in the batch and fluidised bed recovery of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) from unclarified yeast disruptates, exhibited superior capacities and adsorption/desorption performance to the commercial derivatives. These advanced physical and biochemical properties facilitated a demonstration of the direct, mechanical coupling of bead-milling and fluidised bed adsorption in a fully integrated process for the accelerated recovery of G3PDH from yeast. The generic application of such pellicular adsorbents and integrated processes to the recovery of labile, intracellular products is discussed.
Keywords:pellicular adsorbents;fluidised bed adsorption;process intensification;process integration;glyceralclehyde 3-phosphate clehydrogenase;yeast bioprocessing