*2.7. Photochemiluminescence Assay*

In the photochemiluminescence (PCL) assay, superoxide radical anions (O2 •−) were generated from luminol [30]. The antiradical activity against these radicals was determined using the ACL (antioxidant capacity of lipid-soluble substances) kit (Analytik Jena, Jena, Germany). The amaranth extracts were dissolved in methanol to a concentration of 0.25 mg/mL. The portions of 10 μL of solutions were mixed with 2.3 mL of methanol (reagent 1), 200 μL of buffer solution (reagent 2), and 25 μL of luminol (reagent 3). The Photochem device (Analytik Jena) supported by PCLsoft software was used to perform reactions and calculate the results, which were expressed as μmol of Trolox equivalents (TE) per g of extract or per g of FM of plant.
