3.7.3. Total Phenolic Content (TPC) and Total Flavonoid Content (TFC)

TPC was determined using the Folin Ciocalteu colorimetric method [63] with slight modifications. A calibration curve was prepared using a standard solution of gallic acid (0.04, 0.12, 0.2, and 0.28 mg/mL with R² = 0.9988), the samples were performed in triplicates. The standard calibration curve of gallic acid is a linear straight line expressed by the equation y = 3.1973x, R2 = 0.9988 and a slope equals 3.1973 shown in Supplementary Figure S1. Results were expressed as mg gallic acid equivalent (GAE)/g of the dry powder, using UV-visible spectrophotometer (SPECORD 210 plus), Analytik Jena AG, Germany. TFC was evaluated according to the method described by [64]. A calibration curve was prepared using a standard solution of rutin (0.04, 0.08, 0.12, and 0.16 mg/mL with R² = 0.9995), the samples were performed in triplicate. The standard calibration curve of rutin is a linear straight line expressed by the equation y = 0.0062x, R2 = 0.9992 and a slope equals 0.0062 shown in Supplementary Figure S2. Results were expressed on a dry weight basis as mg rutin equivalent/g sample.