Methodology for the determination of biological antioxidant capacity in vitro:: a review

One of the effective means of adding value to agricultural produce is the development of functional foods or dietary supplements enriched with antioxidants. This process involves extraction of antioxidant rich fractions from their sources and then testing for antioxidant activity prior to adding these back to the foods or packing into pills or capsules. Ideally, the antioxidant activity should be tested using both in vitro and in vivo techniques but due to the high cost of conducting animal and human feeding trials, many products undergo only in vitro testing. This review describes popular methods commonly used for testing antioxidant activity in vitro, with particular reference to their reliability, efficiency, accessibility and biological relevance. (c) 2006 Society of Chemical Industry.