Antioxidant activity and total polyphenol content of selected herbal medicinal products used in Poland
The main aim of the study was to evaluate the antioxidant activity and total polyphenol content in fifteen popular herbal products often used in treatment of various diseases. The studied material were, among others, chamomile flower head, oak bark, St. John’s-wort herb, hawthorn flower, dog rose and elder fruits, lingonberry leaf. Herbal extracts or infusions were prepared according to protocols provided by producer on the packaging. The highest antioxidant activity and polyphenols concentration were obtained for lingonberry leaves (725 mg Trolox/g d.w. and 109 mg catechin/g d.w., respectively). The oak bark, St. John’s-wort herb, and lime flower were also a very rich source of antioxidant compounds, independent of their typical therapeutic action. Several herbs, such as dog rose fruit, lose their antioxidant activity when prepared at home conditions.