Determination of total phenolic and flavonoid contents and antioxidant properties of methanolic extract of Mentha aquatique

Today, the use of plant compounds and their derivatives as antioxidants in food and biological systems has been extensively studied in different part of world. Mentha aquatique belongs to the Labiatae family and the genus Mentha and widely found in the north part of Iran. In this study, total Phenolic and flavonoid contents of Mentha aquatique were measured spectrophotometrically and the antioxidant capacity of its methanolic extract were assessed by DPPH radical-scavenging activity, total antioxidant capacity and reducing power assay and were compared with synthetic antioxidant BHT. Total phenolic and flavonoid contents were 52.05±1.1 mg gallic acid eguivalents (GAE)/g extract and 8.33±0.15 mg quercetin eguivalents (QE)/g extract, respectively. The extract showed varying degrees of efficacy in each assay in a dose-dependent manner. The EC50 values of the extract and BHT were 75 and 137.03 μg/ml, respectively. The results of this study showed a good antioxidant activity of the extract and the antioxidant activity showed direct relation with total phenolic and flavonoid compounds. Thus the Mentha aquatique can be used as a good source of natural antioxidants and can be used in food industry.