Protein binding of procyanidins: studies using polyacrylamide gel electrophoresis and French maritime pine bark extract.

The application of PAGE to determine the interaction between procyanidins and proteins, as presented here, enables one to directly determine the binding of either a pure of a complex mixture of flavonoids to a particular protein. If the protein of interest is an enzyme, the combination of PAGE with quantitative activity measurements allows identifying whether a change in the enzyme activity is related to the binding. Data presented suggest that PBE and EGb 761 have protein-binding properties, which, in addition to their redox-based effects, could provide a biochemical basis for their action in biological systems.