title: Removing proteins from an aerated yeast fermentation by pulsing carbon dioxide: replacing salting-out as a method of protein precipitation.
abstract: Salting-out is a common technique used for precipitating proteins and other materials from fermentation and tissue culture processes. It leaves a salt residue in the system. Foam fractionation can also be used to remove proteins by protein precipitation from a dilute solution. In doing so, there is usually a trade-off between enrichment and recovery. An increase in the airflow rate will increase the recovery, but only at the expense of the enrichment. A new method for increasing the recovery in foam fractionations and in yeast fermentations is to add a burst of CO2 to the process and then restore the air. This CO2 acts like a temporary salt, but it does not leave behind a residue. The recovery increases as a result of the joint use of these gases, perhaps by more than 10-fold, without sacrificing the enrichment. Chicken egg albumin in a foam fractionation column can serve as a simple, experimental model for the proposed recovery process in lieu of the fermentation process.
authors.affiliation: Department of Chemical Engineering, Vanderbilt University, Nashville, TN 37235, USA.
authors.forename: Ryan A
authors.initials: RA
authors.lastname: Kirkland
authors.forename: Robert D
authors.initials: RD
authors.lastname: Tanner
mesh_terms: D000388:Air; D002245:Carbon Dioxide / Q000737:chemistry*; D018929:Cell Culture Techniques / Q000379:methods*; D005590:Fractional Precipitation; D012441:Saccharomyces cerevisiae / Q000254:growth & development / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D029701:Saccharomyces cerevisiae Proteins; D002245:Carbon Dioxide