Isolation of lactoperoxidase, lactoferrin, α-lactalbumin, β-lactoglobulin B and β-lactoglobulin A from bovine rennet whey using ion exchange chromatography

A mild and rapid method is described for isolating various milk proteins from bovine rennet whey. beta -Lactoglobulin from bovine rennet whey was easily adsorbed on and desorbed from a weak anion exchanger, diethylaminoethyl-Toyopearl. However, alpha -lactalbumin could not be adsorbed onto the resin. alpha -Lactalbumin and beta -lactoglobulin from rennet whey could also be adsorbed and separated using a strong anion exchanger, quaternary aminoethyl-Toyopearl. The rennet whey was passed through a strong cation exchanger, sulphopropyl-Toyopearl, to separate lactoperoxidase and lactoferrin, alpha -lactalbumin and beta -lactoglobulin were adsorbed onto quaternary aminoethyl-Toyopearl. alpha -lactalbumin was eluted using a linear (0-0.15 M) concentration gradient of NaCl in 0.05 M Tris-HCl buffer (pH 8.5). Subsequently, beta -lactoglobulin B and beta -lactoglobulin A were eluted from the column with 0.05 M Tris-HCl (pH 6.8), using a linear (0.1-0.25 M) concentration gradient of NaCl. The yields were 1260 mg alpha -lactalbumin, 1290 mg beta -lactoglobulin B and 2280 mg beta -lactoglobulin A from 1 1 rennet whey. (C) 2000 Elsevier Science Ltd. All rights reserved.