Fig. 5.
Titration of 3-hydroxyflavone (A), 3′,4′-dihydroxyflavone (B), chrysin (C) and rutin (D) with Fe2+ in 20 mM KPB, pH 7.2. Insets: titration curves. (A), from top to bottom: 10 μM 3-hydroxyflavone in the presence of 0, 2, 4, 6, 8, 10, 12 and 14 μM Fe2+, respectively. (B), from top to bottom: 10 μM 3′4′-dihydroxyflavone in the presence of 0, 2, 4, 6, 8, 10 and 12 μM Fe2+, respectively. (C), from top to bottom: 40 μM chrysin in the presence of 0, 10, 15, 20, 30, 40 and 50 μM Fe2+, respectively. (D), from bottom to top: 10 μM rutin in the presence of 0, 2, 4, 6, 8, 10, 12 and 14 μM Fe2+, respectively.