Degradation changes induced by hydroxyl radicals in bean (Phaseolus vulgaris) and pea (Pisum sativum) proteins

摘要

The oxidative modification of pea and bean proteins caused by hydroxyl radicals was investigated. The changes that occurred during the oxidation process were examined using fluorescence detection and electrophoretic methods. The modification of proteins resulted in a loss of Trp residues and a gain in its degradation product - formylkynurenine (FK); Tyr residues were oxidized to bityrosine (BT). The oxidative modification induced also the formation of protein carbonyl derivatives (PC). The degradation products were observed in minor amounts in pea proteins in comparison to bean proteins. The electrophoretic patterns of bean proteins showed the appearance of new fractions of high molecular weights corresponding to the polymers formation. On the contrary, hydroxyl radical-oxidized pea proteins exhibited a significant reduction in band surface.