Validated Methods for Evaluation of Anti-oxidant Activities of Food

Abstract

Phytochemicals with anti-oxidant activities present in fruits and vegetables such as vitamin C, vitamin E, carotenoids and flavonoids. They are considered to contribute to the protective effect against oxidative stress by scavenging reactive oxygen species (ROS). Evaluation of dietary antioxidants effect, it is important to study the overall effect from all antioxidants in the diet. Validated method is necessary for measuring the total antioxidant capacity of food. Hydrophilic and lipophilic oxygen radical absorbance capacity (H-, and L-ORAC) and singlet oxygen absorption capacity (SOAC) are methods for evaluating antioxidant capacities of hydrophilic and lipophilic compounds. We improved the original method for ORAC and SOAC determination, and evaluated the precision by interlaboratory studies.