Trolox equivalent antioxidant capacity (TEAC) of Ginkgo biloba flavonol and Camelia sinensis catechin metabolites

Only some metabolites from Ginkgo biloba have been studied following the inhibition of chemiluminescence, and the results indicated that metabolites with an o-dihydroxy group in the phenyl ring are as effective as the flavonol-glycoside precursor (rutin) in quenching radicals. Recently, a new approach to establish the relative antioxidant capacity of a variety of polyphenols, including flavonols and catechin gallates, has been introduced. According to this method, the capacity of hydrogen-donors antioxidant to scavenge the ABTS radical cation compared with that of Trolox (TEAC) is assessed. We applied an improved version of this method to establish the TEAC values of main metabolites from G. biloba flavonol-glycosides and green tea catechins, and the results are reported in this communication.