Clarification of Yeast Cell Suspensions by Depth Filtration

Abstract

Depth filtration can be very attractive for initial clarification because of low capital costs and ease of operation. However, there is currently no fundamental understanding of the effects of the filter pore size and morphology on the overall capacity and filtrate quality. The objective of this study was to examine the flux, capacity, and filtrate turbidity of a series of depth filters with different pore size ratings and multilayer structures for the filtration of yeast cell suspensions. Data were analyzed using available fouling models to obtain insights into the flux decline mechanisms. Filters with small pore size provide high filtrate quality at low capacity, with the reverse being true for the larger pore sizes. The multilayer structure of commercial depth filters leads to improved performance, although the choice of layer properties is critical. The highest capacity was achieved using a multilayer filter in which the upper layer allows significant yeast cell penetration into the filter matrix but still protects the retentive layer that is needed for a high quality filtrate.

Effect of L-isoleucine and L-phenylalanine Addition on Aroma Compound Formation During Longan Juice Fermentation by a Co-culture of Saccharomyces cerevisiae and Williopsis saturnus

“…The juice was stored at -20°C before use, which can prolong the shelf life without changing the composition of the juice into a soluble solids concentration and titratable acidity (Jiang, 1999). The longan juice was sterilised by aseptic micro-filtration through a 0.45 µm pore size micro-filter (Sartorius, Germany), which can retain the yeast cells and thus remove wild yeasts initially present in the juice (Chandler & Zydney, 2005). Furthermore, a sterility check was done by plate counting.…”

Effects of solution environment on mammalian cell fermentation broth properties: Enhanced impurity removal and clarification performance

“…The clarification of recombinant proteins such as monoclonal antibodies and Fc‐fusion proteins from manufacturing‐scale bioreactors containing mammalian cells is usually performed using either filtration or centrifugation. The filtration process is typically operated in a tangential‐flow mode using microfiltration (MF) membranes although depth filtration in a dead‐end mode is also common (Chandler and Zydney, 2005). In addition, traditional downstream processing of therapeutic proteins has been designed to place nearly all of the purification capabilities on chromatography steps with the clarification steps designed exclusively for cell and cell debris removal.…”

A modular approach for the ultra-scale-down of depth filtration

“…To produce the samples, centrate was processed over four different depth filters (three adsorptive, one steric) to generate samples with a range of particulate concentrations. Depth filters with different pore size and morphologies yield filtrate of varying quality [30].…”