Interaction of beta-lactoglobulin with resveratrol and its biological implications.
Beta-lactoglobulin (beta-LG), the major whey protein in the milk of ruminants, has a high affinity for a wide range of compounds. Resveratrol (3,5,4'-trihydroxystilbene), a natural polyphenolic compound found in grapes and red wine, exhibits many physiological effects associated with health benefits. In this study, the interaction of resveratrol with beta-LG was investigated using circular dichroism, fluorescence and UV-vis absorbance. Self-association of resveratrol possibly occurs at high concentrations. Resveratrol interacts with beta-LG to form 1:1 complexes. Resveratrol is bound to the surface of the protein because beta-LG-bound polyphenol is in a weaker hydrophobic environment relative to 75% ethanol. The binding constant for the resveratrol-beta-LG interaction is between 10(4) and 10(6) M (-1), as determined by protein or polyphenol fluorescence. The beta-LG-resveratrol interaction may compete with self-association of both the polyphenol and the protein. It has no apparent influence on beta-LG secondary structure but partially disrupts tertiary structure. Complexing with beta-LG provides a slight increase in the photostability of resveratrol and a significant increase in its hydrosolubility.
Liang
Li
L
Chaire de recherche du Canada sur les protéines, les bio-systèmes et les aliments fonctionnels, Institut de recherche sur les nutraceutiques et les aliments fonctionnels (INAF/STELA), Université Laval, Sainte-Foy, Canada.
Tajmir-Riahi
H A
HA
Subirade
Muriel
M
D001682:Biological Availability; D002942:Circular Dichroism; D007782:Lactoglobulins / Q000737:chemistry*; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D000077185:Resveratrol; D012995:Solubility; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013267:Stilbenes / Q000737:chemistry* / Q000493:pharmacokinetics / Q000494:pharmacology
D007782:Lactoglobulins; D013267:Stilbenes; D000077185:Resveratrol