Resveratrol-β-lactoglobulin interaction studied by circular dichroism and fluorescence

AGFD 169

Li Liang, liliang_bm@yahoo.com, Department of Food Science and Nutrition, University Laval, Pavillon Paul Comtois, Quebec, QC G1K 7P4, Canada and Muriel Subirade, muriel.subirade@aln.ulaval.ca, Canada Research Chair in proteins, bio-systems and functional food, Department of Food Science and Nutrition, University Laval, Pavillon Paul Comtois, Quebec, QC G1K 7P4, Canada.
β-Lactoglobulin (β-LG), the major whey protein in the milk of ruminant, 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, including anti-oxidant, anti-flammatory and anti-platelet aggregating actions. In this study, the interaction of resveratrol with β-LG is investigated using circular dichroism and fluorescence. Resveratrol can interact with β-LG to form 1:1 complexes, which has no apparent influence on the secondary structure of β-LG but partly destroys the tertiary structure of β-LG. The binding constants are between 104 and 106 M-1, indicating that the interaction of resveratrol with β-LG is a non-specific binding. After interacting with β-LG, resveratrol transfers from a hydrophilic environment in the aqueous solution to a more hydrophobic environment, which hydrophobicity is much weaker than 75% ethanol. These results suggest that resveratrol molecules are bound in the surface of β-LG.
 

General Posters
1:00 PM-3:00 PM, Tuesday, August 21, 2007 BCEC -- Exhibit Hall - B2, Poster

Division of Agricultural & Food Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007