Analysis of Lactosylated β-Lactoglobulin by Capillary Electrophoresis

J. Otte (1) , K.S. Larsen (1) , Said Bouhallab (2)

1 Department of Dairy and Food Science
2 STLO - Science et Technologie du Lait et de l'Oeuf

Variously lactosylated species of b-lactoglobulin AB were analysed by capillary electrophoresis at low pH and high pH with and without bu¤er additives. By simple capillary zone electrophoresis at either low or high pH the lactosylated forms had longer migration times than the native b-lactoglobulin, most likely due to their larger molecular size and lower pI. By micellar electrokinetic chromatography using SDS as detergent the lactosylated forms of b-lactoglobulin had shorter migration times than the native species, due to less interaction with the micelles. The methods used were also able to distinguish between more or less lactosylated forms of b-lactoglobulin. By all methods used, partial separation of at least Þve forms of b-lactoglobulin were obtained. However, baseline separation of b-lactoglobulin with varying number of lactose units attached was not obtained, probably due to the presence of both variants of b-lactoglobulin with various numbers of lactosyl groups at di¤erent sites

Mots clés: b-lactoglobulin; capillary electrophoresis; lactosylated; ²-lactoglobulin

Mots clés: lactosylation; électrophorèse capillaire; technologie laitière; beta lactoglobuline

Domaines: Alimentation et Nutrition; Ingénierie des aliments

J. Otte, K.S. Larsen, Said Bouhallab. Analysis of Lactosylated β-Lactoglobulin by Capillary Electrophoresis. International Dairy Journal, 1998, 8 (10-11), pp.857-862. ⟨10.1016/S0958-6946(98)00128-9⟩. ⟨hal-01559702⟩