Total Phenolic Contents and Antioxidant Activities of Different Herbal Tea Extracts from Turkey

Abstract

: The aim of the present study is to determine the total phenolic contents (TPC), DPPH radical scavenging activities, and reducing power of commercially consumed herbal teas including sage tea (ST), blackberry tea (BT), apple tea (AT), Echinacea tea (ET), lime tea (LT), rosehip tea (RT), and green tea (GT) in Turkey. For this purpose, various solvents were used for extraction of the tea samples and the results were compared in terms of total phenolic contents and antioxidant activities, as well. Hot water is found as the best solvent for the extraction of total phenolics from ST, BT, AT, and RT, respectively. On the other hand, the highest TPC values are obtained with the extraction of ET, LT, and GT in the presence of aqueous acetone (50%) solvent system. Generally all samples gave high DPPH radical scavenging activities depending on their extraction solvents. The highest radical scavenging activity was found as 94.92 ± 0.01 % for ST in ethanol, while the lowest activity was obtained as 5.98 ± 0.14 % for BT with water extract. Ferric reducing antioxidant assay results are closed each other and the highest activity (0.27 ± 0.74 mM Trolox) was observed in the ethanol extract of ST. Antioxidant activities and TPC of the herbal tea samples varied depending on the extraction solvent. Water or aqueous organic solvent extracts of sage tea and green tea samples gave high TPC values and antioxidant activities.