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Updated: Jun 28, 2026

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
Fast repair activities towards dGMP hydroxyl radical adducts by silybin and its analogues
Haiying Fu1, Yosuke Katsumura, Mingzhang Lin
1Nuclear Professional School, School of Engineering, The University of Tokyo, Tokaimura, Nakagun, Ibaraki, Japan.
Abstract:
The repair activities of silybin (SLB) and its analogues towards the oxidizing deoxyguanosine monophosphate (dGMP) hydroxyl radical adducts are investigated by pulse radiolytic techniques. On pulse irradiation of nitrous oxide saturated 2.0 mM dGMP aqueous solution containing 0.1 mM silybin at neutral pH, the transient absorption spectrum of the dGMP hydroxyl radical adducts decreases with the formation of the phenoxyl radical of silybin within tens of microseconds, indicating that there is a repair reaction between the dGMP hydroxyl radical adduct and silybin. The rate constant of the repair reaction is calculated to be 1.0 x 10(9) M(-1)s(-1) for silybin. The repair activity of hesperetin (HESP), naringin (NAN) and naringenin (NAR) towards hydroxyl radical adducts of dGMP are also studied.
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