“…The strength of antioxidant activity depends on the number of hydroxyl groups possessed, such as quercetin, which will provide stronger activity than naringenin and apigenin with three hydroxyl groups [ 116 , 117 , 121 ]. This is indicated by the value of IC 50 that is smaller and TEAC values that are larger compared to the two compounds with each IC 50 (10.89 ± 0.03; >1000; 463.40 ± 22.28 µM) and TEAC (4.7, 1.53, 1.45 mM) [ 118 , 119 , 120 , 121 , 122 , 123 , 124 , 125 , 126 , 127 , 128 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 ]. At the same time, the formation of a resonance-stabilized quinone structure due to the hydroxyl group adjacent to the ring C [ 125 ].…”