Reactions of plant phenols with myoglobin: Influence of chemical structure of the phenolic compounds

The reaction products of myoglobin and simple phenolic compounds, with different configurations of hydroxyl groups, and p-quinone were characterized in terms of selected properties (electrophoretic, chromatographic and mass spectrometric) and by in vitro digestion. The o-, and p-hydroxyphenols, p-quinone and gallic acid showed high reactivity leading to structural changes in myoglobin. In comparison, ferulic acid and m-hydroxyphenol reacted to only a small extent, especially affecting tryptophan fluorescence of myoglobin. The enzymatic digestion (tryptic, alpha -chymotryptic, peptic and pancreatic), on the basis of in vitro experiments with derivatized myoglobin, was adversely influenced.