Binding Interactions Between α-glucans from Lactobacillus reuteri and Milk Proteins Characterised by Surface Plasmon Resonance

Silja Kej Diemer, Birte Svensson, Linnéa N. Babol, Darrell Cockburn, Pieter Grijpstra, Lubbert Dijkhuizen, Ditte M. Folkenberg, Christel Garrigues, Richard H. Ipsen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    Interactions between milk proteins and α-glucans at pH 4.0–5.5 were investigated by use of surface plasmon resonance. The α-glucans were synthesised with glucansucrase enzymes from Lactobacillus reuteri strains ATCC-55730, 180, ML1 and 121. Variations in the molecular characteristics of the α-glucans, such as molecular weight, linkage type and degree of branching, influenced the interactions with native and denatured β-lactoglobulin and κ-casein. The highest overall binding levels were reached with α-(1,4) compared to α-(1,3) linked glucans. Glucans with many α-(1,6) linkages demonstrated the highest binding levels to κ-casein, whereas the interaction with native β-lactoglobulin was suppressed by α-(1,6) linkages. Glucans with a higher degree of branching generally displayed lower protein binding levels whereas a higher molecular weight resulted in increased binding to κ-casein. The interactions with κ-casein were not pH dependent, whereas binding to denatured β-lactoglobulin was highest at pH 4.0 and binding to native β-lactoglobulin was optimal at pH 4.5–5.0. This study shows that molecular weight, linkage type and degree of branching of α-glucans highly influence the binding interactions with milk proteins.
    Original languageEnglish
    JournalFood Biophysics
    Volume7
    Issue number3
    Pages (from-to)220-226
    ISSN1557-1858
    DOIs
    Publication statusPublished - 2012

    Cite this

    Diemer, S. K., Svensson, B., Babol, L. N., Cockburn, D., Grijpstra, P., Dijkhuizen, L., Folkenberg, D. M., Garrigues, C., & Ipsen, R. H. (2012). Binding Interactions Between α-glucans from Lactobacillus reuteri and Milk Proteins Characterised by Surface Plasmon Resonance. Food Biophysics, 7(3), 220-226. https://doi.org/10.1007/s11483-012-9260-5