title: Comparison of scavenging capacities of vegetables by ORAC and EPR.
abstract: Reactive oxygen species (ROS) are considered to be causative agents of many health problems. In spite of this, the radical-specific scavenging capacities of food samples have not been well studied. In the present work, we have developed an electron paramagnetic resonance (EPR) spin trapping method for analysis of the scavenging capacities of food samples for multiple ROS, utilising the same photolysis procedure for generating each type of radical. The optimal conditions for effective evaluation of hydroxyl, superoxide, and alkoxyl radical scavenging capacity were determined. Quantification of radical adducts was found to be highly reproducible, with variations of less than 4%. The optimised EPR spin trapping method was used to analyse the scavenging capacities of 54 different vegetable extracts for multiple radicals, and the results were compared with oxygen radical absorption capacity values. Good correlations between the two methods were observed for superoxide and alkoxyl radicals, but not for hydroxyl.
authors.affiliation: National Food Research Institute, National Agriculture Research Organization, 2-1-12 Kannondai, Tsukuba-shi 305-8642, Ibaraki, Japan. Electronic address: hkameya@affrc.go.jp.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Kameya
authors.forename: Jun
authors.initials: J
authors.lastname: Watanabe
authors.forename: Yuko
authors.initials: Y
authors.lastname: Takano-Ishikawa
authors.forename: Setsuko
authors.initials: S
authors.lastname: Todoriki
mesh_terms: D000438:Alcohols / Q000037:antagonists & inhibitors; D003497:Cyclic N-Oxides / Q000737:chemistry; D004032:Diet / Q000208:ethnology; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000032:analysis* / Q000737:chemistry; D005638:Fruit / Q000737:chemistry; D055951:Functional Food / Q000032:analysis*; D017665:Hydroxyl Radical / Q000037:antagonists & inhibitors; D007202:Indicators and Reagents / Q000737:chemistry; D007564:Japan; D007700:Kinetics; D010782:Photolysis; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors*; D015203:Reproducibility of Results; D019097:Spin Trapping; D013481:Superoxides / Q000037:antagonists & inhibitors; D014675:Vegetables / Q000737:chemistry*
chemical_list: C516729:5-(2,2-dimethyl-1,3-propoxy cyclophosphoryl)-5-methyl-1-pyrroline N-oxide; D000438:Alcohols; D003497:Cyclic N-Oxides; D016166:Free Radical Scavengers; D007202:Indicators and Reagents; D010936:Plant Extracts; D017382:Reactive Oxygen Species; C059688:alkoxyl radical; D013481:Superoxides; D017665:Hydroxyl Radical
keywords: Alkoxyl radical; Electron paramagnetic resonance spectroscopy; Hydroxyl radical; Oxygen radical absorbance capacity (ORAC); Superoxide radical