An oxygen radical absorbance capacity (ORAC) assay was conducted per the method in the literature65 (link). Briefly, 100 μL of fluorescein (10 μM) and a 50 μL sample (0.1 mg/mL) of Trolox (15–250 μM) were transferred into a 96-well plate. Subsequently, 50 μL of 2, 2’-azobis(2-methylpropionamidine) dihydrochloride (500 mM) was added and the fluorescence of the mixture was recorded for 2 h at 485-nm excitation and 528-nm emission in a Synergy LX microplate reader (BioTek, Winooski, VT, USA). The ORAC was reported in terms of micromoles of Trolox equivalents (TE) per gram of dry RPH sample (µmol TE/g RPH)65 (link).
Free full text: Click here
