Free radical scavenging activity of extract from Ilex rotunda determined by electron spin resonance spectroscopy

Antioxidant activity of the extract from the barks of Ilex rotunda was investigated using electron spin resonance (ESR) spectroscopy on 1,1-diphenyl-2-picrylhydrazyl (DPPH), alkyl, hydroxyl, and superoxide radicals. The extract exhibited strong free radical scavenging activity with scavenging percentages of DPPH radical (82.2 ± 1.8%), alkyl radical (82.9 ± 1.7%), hydroxyl radical (89.9 ± 2.1%), and superoxide radical (92.5 ± 2.6%) at concentration of 50 μg/ml, respectively. Activity increased with increasing extract concentrations. Therefore, these results presented the extract from the barks of I. rotunda with a potent antioxidant activity that could be useful in food, pharmaceutical, and cosmetic industries. Key words: Ilex rotunda, antioxidant, free radical scavenging activity, electron spin resonance.