Purity and Yield of β-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%) β-lactoglobulin from bovine acid whey. Conditions for producing a potentially hypoallergenic reduced β-lactoglobulin whey were investigated. Reapplication of pH 5.1 eluate to the column resulted in a final purity of 87% α-lactalbumin. The purity of β-lactoglobulin was slightly lower upon elution with buffers containing <0.4 M sodium phosphate, whereas the yield from desorbing buffers <0.1 M 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 β-lactoglobulin. These findings suggest that the retinal matrix shows promise in its application for creating hypoallergenic products and the isolation of high-purity β-lactoglobulin with useful functional properties.