Total phenolic content

Itoshima city has a temperate climate that is suitable for growing vegetables, fruits, and flowers due to the influence of the Tsushima Current. As a result, various agricultural products are grown in the region throughout the year. In this study, we investigated the antioxidant activity of agricultural products grown around Itoshima city. The activity not only of the edible part but also of by-products such as peal, leaf, branch, and root were evaluated. Water extracts and ethanol extracts were prepared from the freeze-dried materials of each agricultural product, and their oxygen radical absorbance capacity (ORAC), DPPH radical scavenging activity, ferromagnetic ion reducing power ability, and total phenolic contents were measured. Results showed that extract prepared from the by-products of the Amaou strawberry, including the stron, flower, and root showed extremely high activity among all samples. In the other fruits and vegetables tested, the extract prepared from by-products also showed higher activity than those of edible parts. These findings suggest possible new uses for the by-products of natural materials grown in the Itoshima region based on their potential bioactivities, and indicate the potential for development of a local industry based on healthy food and cosmetics.