Antioxidant activity of Trachystemon orientalis (L.) G. Don (Borage) grown and eaten as food in Ordu, Turkey
Abstract
Introductıon: Instead of synthetic antioxidants, using of natural products with antioxidant
activity is demanded. Objectıve: The aim of this study is to evaluate the antioxidant
activity and total phenolic and flavonoid contents of the Trachystemon orientalis (borage)
obtained from Ordu. Methods: The water and ethanol extracts of the borage plant were
investigated by using several in vitro antioxidant activity tests such as total antioxidant
capacity, O2
•-, •OH, DPPH and ABTS radicals scavenging activities, hydrogen peroxide scavenging
activity, FRAP, Fe2+ chelating and reducing power assays in order to make effective
comparisons. Results: Water extract of the T. orientalis had the more phenolic (90 mg GA/g
extract) and flavonoid (56.88 mg CT/g extract) contents than ethanol extract. Furthermore,
both of the extracts showed strong antioxidant and radical scavenging activities determined
by different in vitro models. The highest total antioxidant capacity as ascorbic acid
equivalents of 244.50 mg/g extract was also calculated for water extract. Generally, a relationship
between total phenolic content and antioxidant activity was established. It is also
an important finding for an edible food source that the phenolic and flavonoid content and
antioxidative activities for water extract was higher than the ethanol extract. Conclusıon:
T. orientalis could be used as a food ingredient instead of synthetic antioxidants and all
results will contribute to the recent increase in investigations on using natural products in
many areas such as food, pharmacy, alternative medicine and natural therapy.