The antioxidant activities of water, ethanol, and ether extracts of the leaves of Cydonia vulgaris Pers. were determined by the thiocyanate method. The antioxidant activity of water extract was increased with the increasing amount of extract (200 µg-1000µg) added to the linoleic acid emulsion. Ether extract was the most effective antioxidant among the extracts. Like antioxidant activity, the reducing power of water extract was concentration dependent. However, ethanol extract was the highest in reducing power, and ether extract was the lowest. The results obtained in the present study indicate that the leaves of Cydonia vulgaris are a potential source of natural antioxidants. In addition, we could suggest that although the reducing power of a substance may be an indicator of its potential antioxidant activity, there is not necessarily a linear correlation between these two activities.

The antioxidant activities of water, ethanol, and ether extracts of the leaves of Cydonia vulgaris Pers. were determined by the thiocyanate method. The antioxidant activity of water extract was increased with the increasing amount of extract (200 µg-1000µg) added to the linoleic acid emulsion. Ether extract was the most effective antioxidant among the extracts. Like antioxidant activity, the reducing power of water extract was concentration dependent. However, ethanol extract was the highest in reducing power, and ether extract was the lowest. The results obtained in the present study indicate that the leaves of Cydonia vulgaris are a potential source of natural antioxidants. In addition, we could suggest that although the reducing power of a substance may be an indicator of its potential antioxidant activity, there is not necessarily a linear correlation between these two activities.