3.7. Cellular Antioxidant Assay

A cell-based assay for testing the antioxidant activity of phytochemicals was adopted from Wolfe and Liu [24] with some modifications as described in our previous paper [7]. Cellular antioxidant activity (CAA) was determined as:

where:

AUC_s is the integrated area under the sample fluorescence versus time curve;

AUC_c is the integrated area under the control fluorescence versus time curve;

Fluorescence excitation was measured at 485 nm and fluorescence emission was measured at 520 nm every 5 min for 12 cycles at 37 °C.