Flavonoids as Putative Inducers of the Transcription Factors Nrf2, FoxO, and PPARγ

Figure 4

Graph showing the antioxidant capacity of the flavonoids and vitamins tested compared to trolox in assays using the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical (a) and the ferric-reducing ability of plasma (FRAP) (b). (a) The reduction of the coloured ABTS radical is plotted as the difference in absorbance to the vehicle control against the concentration of the compound that was added to the reaction. Absorbance was measured at 690 nm after 6 minutes. (b) The absorbance of a solution containing a known concentration of ferrous ions is plotted against the flavonoid or vitamin concentration. Absorbance was measured at 620 nm after 15 minutes incubation. The legends show the flavonoid with the steepest curve first and the shallowest last. que: quercetin; kae: kaempferol; fis: fisetin; gen: genistein; dai: daidzein; nar: naringenin; hes: hesperetin; lut: luteolin; api: apigenin; asc-a: ascorbic acid, a-toc: α-tocopherol. compared to trolox, compared to trolox.

(a)

(b)