Reassessment of Antioxidant Activity of Baicalein in vitro.

Xiaozhen Wang; Xican Li; Hongrui Li

Objective: Although the antioxidant of baicalein has previously been investigated by several assays, the results seemed conflicting with each other. Therefore, the present study tried to systematically reassess its antioxidant in vitro, to bring about more reliable results and explain its antioxidant mechanism. Methods: The antioxidant activity of baicalein in vitro was reassessed using ferric ions (Fe3 ) and cupric ions (Cu2 ) reducing power, hydroxyl radical (• OH) and superoxide anion radical (O2• - ) scavenging activities, lipid peroxidation,1,1-diphenyl-2-picryl-hydrazyl (DPPH• ), 2,2' -azino-bis (3-ethylbenzthiazoline-6- sulfonic acid) (ABTS • ), ferrous ions (Fe2 ) and cupric ions (Cu2 ) chelating activities, compared with an identical positive control Trolox. Results: Baicalein exhibited antioxidant effects in dose-dependent manners, the IC50 values of baicalein were calculated as 7.01±0.23, 4.58±0.05, 25.32±0.44, 18.63±0.15, 11.74±0.43, 4.75±0.14, 1.38±0.04, 2.18±0.11, 32.50±2.51 μ g/mL, respectively, for reducing power (Fe3 ), reducing power (Cu2 ), hydroxyl radical scavenging, superoxide anion radical scavenging, lipid peroxidation, DPPH, ABTS, chelating ability (Fe2 ) and chelating ability (Cu2 ). Except for DPPH, its IC50 values were significantly (P<0.01) lower than Trolox, suggesting baicalein was a more effective antioxidant than Trolox. Conclusion: Contrary to the previous reports, baicalein shows higher reducing power and • OH scavenging ability. Generally, baicalein is a stronger antioxidant than Trolox, according to the IC50 values. It may exhibit antioxidant activities by both chelating metal transition ions as well as by scavenging free radicals via donating hydrogen atom (H• ) or electron (e). Therefore, baicalein may be a potential candidate for use as natural antioxidant in pharmaceutical, food and biological industry.

THERAPEUTIC use of antioxidants; PHYSIOLOGICAL effects of ferrous sulfate; HYDROXYL group; CHELATION therapy; HYDROGEN; PEROXIDATION

Asian Journal of Pharmaceutical & Biological Research (AJPBR), 2011, Vol 1, Issue 2, p186

2231-2218

Academic Journal