Evaluation of the ESR spin trapping method of reactive-oxygen-species scavenging of tomato juice with different color tones

Abstract

  Using the electron spin resonance spin trapping method, we evaluated the reactive-oxygen-species (hydroxyl radicals, alkoxy radicals, superoxide radicals and singlet oxygen) scavenging abilities of 41 tomato juice samples with different color tones. There was no significant difference in the reactive oxygen scavenging ability between the dark red, red, pink and yellow samples. However, the dark red sample had a significantly higher singlet oxygen scavenging ability than the red one. For these color tones of tomatoes, the hydroxyl radical and the singlet oxygen scavenging abilities are related to the color tone of the appearance. The alkoxyl and superoxide radicals scavenging abilities have correlation with color tones. However, we cannot explain why the lycopene and β-carotene alone cannot explain the relevance. Therefore, we estimated that other antioxidant components are involved. On the other hand, the lemon-colored one had significantly higher alkoxy radical, superoxide radical, and singlet oxygen scavenging ability than conventional tomato juice which has already been circulated. We expected the lemon-colored tomato had new functionality.