Antioxidant and antidiabetic potency of yogurts supplemented with aqueous extracts of two medicinal plants during storage

In the present study, the effects of adding aqueous extracts from two medicinal plants, <i>Achillea odorata</i> and <i>Phlomis crinita</i>, on total phenolic content, antioxidant activity (measured by DPPH and ferric reducing assays), and the ability to inhibit α-amylase and α-glucosidase activity were investigated over 21 days of refrigerated storage at 4 °C. Our results showed that the addition of the plant extracts affect the phenolic content. The enriched yogurts presented significantly (<i>p</i> ˂ 0.05) higher polyphenol contents. Also, during refrigerated storage time, yogurts fortified with plant extracts had higher DPPH radical scavenging capacity and reducing power effect than plain yogurt. In addition, higher inhibition of α-amylase and α-glucosidase by fortified yogurts compared to control yogurt occurred with maximum activities at the 14th day of storage. These results suggest that <i>A. odorata</i> and <i>P. crinita</i> leaves may be useful as a natural ingredient for improving the antioxidant and antidiabetic activity of yogurt.