2.5. Total Antioxidant Status (TAS) assay
The TAS assay was carried out using Cayman’s Antioxidant Assay Kit. Into the each of the sample wells, 10 μL
of three series of concentrations including 500; 125; 31.25 μg/mL of GMRextract and fractions, 10 μL
metmyoglobin, and 150 μL chromogen were added. For Trolox standard wells, 10 μL trolox standard (tubes A-G),
metmyoglobin, and 150 μL chromogen were put. To intitiate the reactions, 40 μL hydrogen peroxide was added into
all wells. The plate was incubated on a shaker for 5 minutes at room temperature. Absorbance was read at 750 nm
using Elisa Reader. The TAS was calculated using the linear regression equation of the standard curve written in the
following equation3
.
x dilution
slope
absorbance y ercept TAS mM . int )