Amaranth Extracts' Impact on RAW 264.7 Cell Viability

The viability of RAW 264.7 cells incubated with variable concentrations of amaranth extracts was assayed with MTT test. Cells (5 × 10⁵ cells/well) were seeded onto the 96 multi-well plates (Sarstedt, Numbrecht, Germany) and kept for 24 h as adherent cultures at 37 °C. Then, different dry methanol amaranth extracts dissolved in DMSO were added to the appropriate cell wells, and incubation was performed for 24 h. Six concentrations of amaranth extracts: 1 mg/mL; 500 μg/mL; 100 μg/mL; 10 μg/mL; 1 μg/mL; 0.1 μg/mL of medium were tested. The cells cultured in medium were used as positive control (100 % of growth), whereas the cells incubated with addition of 20 mM/L hydrogen peroxide to medium provided the negative control (0 % of growth). The test was conducted as described previously [32 (link)]. The absorbance was measured at 550 nm (the reference wavelength of 690 nm) using Universal Microplate Reader ELX800NB (Bio-Tek Instruments INC, Winooski, VT, USA). The following formula was applied to report the results: (average OD value over three measurements for each experimental group/average OD value of control group) × 100 %. Each experiment was repeated in triplets.