Effect of apple components on the production of intracellular ROS during aging. MCY4/Kllsm4::KanMX4 yeast cells were grown in the presence of extracts from the peel, flesh, or entire apple and the polyphenolic fraction. Acetone was used as a control. Cells from exponential (EXP; (a)) and stationary (STAT; (b)) cultures were incubated with DHR123 and after 3 h observed at the fluorescence microscope. In (c) is reported the percentage of ROS positive cells. Average and standard deviations, obtained from three independent experiments, are also indicated.