Analysis of the interaction of food components with model lingual epithelial cells: the case of sweet proteins

We have developed a device that analyses the interaction of food components with model epithelial cells using surface plasmon resonance (SPR). A model of epithelial lingual cells was devised using a liposome composed of a mixture of four phospholipids. The liposome was immobilised to the L1 sensor tip attached to the sensor port of the SPR system. The interaction of food components with the model lingual epithelial cells was determined by the patterns of sensorgrams. According to this method, food components were classified into three groups: group A, strong interaction with the lipid bilayer; group B, weak interaction; and group C, neither A-nor B-type interaction. The sensorgrams of group A showed gradual binding and slow dissociation from the surface of the lipid bilayer. In group B, the food components showed rapid binding and rapid dissociation from the lipid bilayer. The compounds in group C exhibited weak binding to the lipid bilayer, but parts of these samples formed rigid complexes with the lipid bilayer. Sweet proteins producing prolonged sweetness perception as well as miraculin with its taste-modifying activity were classified into group A. The sensory activities of these substances are probably induced by their strong interactions with the epithelial cell surface; they have distinct binding constants with the lipid bilayer. Thaumatin exhibited the strongest interaction, followed by monellin and miraculin. Copyright (C) 2011 John Wiley & Sons, Ltd.