2.3.8. Hydroxyl Radical Scavenging Activity (•OH-RSA)

The Fenton-type reaction method of Smirnoff and Cumbes [17] was used to determine ^•OH-RSA with some modifications. A 50 μL extract was mixed with 50 μL of 6 mM FeSO₄·7H₂O and 50 μL of 6 mM H₂O₂ (30%), followed by incubation at 25 °C for 10 min. After incubation, 50 μL of 6 mM 3-hydrooxybenzoic acid were added and absorbance was measured at a wavelength of 510 nm. Ascorbic acid from 0 to 300 μg/mL was used to obtain a standard curve and data was presented in mg AAE/g.