2.3.2. Quantification of total monomeric anthocyanin content (TAC)Total anthocyanins content of the extract was determined by pH- differential method following the protocol of Chen et al. (2020) with slight modifications. Briefly, samples were mixed in potassium chloride (0.10 M) buffer of pH 1.0 and sodium acetate (0.5 M) buffer of pH 4.5. These two solutions were allowed to equilibrate for 15 min at room temperature. The absorbance of the solutions was measured at 520 nm and 700 nm, respectively, in a UV–Vis-spectrophotometer (UV–Vis spectrophotometer, Model: UV5704SS) against distilled water (blank). Cyanidin 3- glucoside was used as a standard and the results were expressed as milligrams Cyanidin 3- glucoside equivalents/litre. TAC was calculated using the following formula.