Examination of antioxidant activity of Ginkgo biloba leaf infusions

The antioxidant capacity, AOC, of Ginkgo biloba leaf infusions was determined and compared using FRAP and ABTS assays. Capillary electrophoresis was used for the determination of flavonoids in G. biloba leaves to confirm and elucidate the fingerprint compounds that contribute to the AOC. Various parameters in the preparation of the infusion, such as degree of fermentation, surface area of leaves, temperature and time of leaves infusion have been considered, in order to determine their effects on the AOC. It was found that fermentation had no significant effect on the AOC of the G. biloba leaves. However, increased surface area of leaves (leaves ground for 20 s), an infusion temperature of 100 °C and infusion time around 10–15 min gave the highest overall AOC.