Partial removal of proteins from lactic acid fermentation broth and recovery of proteins from brewery wastes by foam fractionation technique

Kurt, Lütfiye
Foam separation is a simple and economic method for separation of surface-active molecules such as proteins and enzymes from aqueous solutions. In this study, lactic acid broth, spent brewer’s yeast extract and residual beer was used to investigate the applicability and efficiency of foam separation technique in partial purification of fermentation products and recovery of valuable components from industrial waste streams. The effects of the process variables initial feed concentration, air flow rate, foaming time, liquid pool height and temperature on separation performance were studied and optimum conditions for removal of proteins from lactic acid broth was determined. Highest enrichment (172.2) and separation ratio (314) with a high protein recovery (45.2 %) were obtained by foaming 200 ml of lactic acid broth with an initial feed concentration of 0.018 mg/ml at an air flow rate of 38.5 cm3/min. Selectivity of foam separation in protein purification, and its effect on protein structure was investigated in brewery wastes using SDS-PAGE and native PAGE, respectively.


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BOZOGLU, F; OZILGEN, M; BAKIR, U (Elsevier BV, 1987-09-01)
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Citation Formats
L. Kurt, “Partial removal of proteins from lactic acid fermentation broth and recovery of proteins from brewery wastes by foam fractionation technique,” M.S. - Master of Science, Middle East Technical University, 2006.