Purity and yield of beta-lactoglobulin isolated by an N-retinyl-Celite bioaffinity column

A bioaffinity column of all-trans-retinal immobilized on Celite was capable of isolating high-purity (94.5%) beta-lactoglobulin from bovine acid whey. Conditions far producing a potentially hypoallergenic reduced beta-lactoglobulin whey were investigated. Reapplication of pH 5.1 eluate to the column resulted in a final purity of 87% alpha-lactalbumin. The purity of beta-lactoglobulin was slightly lower upon elution with buffers containing <0.4 M sodium phosphate, whereas the yield from desorbing buffers <0.1 Ni decreased to approximately 40% of that obtained with 0.4 M sodium phosphate. Desorption with low phosphate concentration was improved when pH was increased, suggesting that desorption involves titration of a protophilic group on beta-lactoglobulin. These findings suggest that the retinal matrix shows promise in its application for creating hypoallergenic products and the isolation of high-purity beta-lactoglobulin with useful functional properties.