FIG. 1.

NQO1 activity is induced by the AHE and its fractions in Hepa1c1c7 cells. (A) Measurement of AHE-induced QR activity in Hepa1c1c7 cells. The cells were treated with the indicated concentrations of the AHE (0–100 μg/mL) for 24 h. The cell survival ratio (%) (B) and specific QR activity (C) of the four AHE fractions in Hepa1c1c7 cells. Each value represents the mean±SD from three independent experiments. NQO1, NAD(P)H dehydrogenase (quinone 1); AHE, ethanolic extract of Adenocaulon himalaicum; QR, quinone reductase; SD, standard deviation.