Electrocatalytic evaluation of DNA damage by superoxide radical for antioxidant capacity assessment

• Published in: Journal of electroanalytical chemistry (Lausanne, Switzerland) Vol. 659; no. 1; pp. 43 - 49
• Main Authors: Barroso, M.F., de-los-Santos-Álvarez, N., Lobo-Castañón, M.J., Miranda-Ordieres, A.J., Delerue-Matos, C., Oliveira, M.B.P.P., Tuñón-Blanco, P.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.08.2011; Elsevier
• Subjects: adenine; antioxidant activity; Antioxidant capacity; antioxidants; Ascorbic acid; beverages; Biological and medical sciences; Biosensors; Biotechnology; carbon; catalysts; DNA; DNA damage; electrochemistry; electrodes; Food industries; Fundamental and applied biological sciences. Psychology; guanine; Methods. Procedures. Technologies; NAD (coenzyme); NADH electrocatalysis; Non alcoholic beverage industries and mineral waters; oligonucleotides; oxidation; oxygen; Reactive oxygen species; superoxide anion; Superoxide radical; Various methods and equipments; xanthine; xanthine oxidase; AA; RES; Reactive oxygen species; Ascorbic acid; TPC; DNA damage; Antioxidant capacity; SOD; Superoxide radical; XOD; SSPE; AOC; ROS; CPE; GA; dA 21; SAM; CA; NADH electrocatalysis; Adenine derivatives; Purine nucleotide; Oxidative stress; Purine derivatives; Vitamin; Antioxidant; Carbon; Electrochemical detector; Electrocatalysis; NADH; Biosensor; DNA; Paste electrode; Oligonucleotide; Superoxide radicals; Lesion; Beverage; Modified material
• ISSN: 1572-6657; 1873-2569
• DOI: 10.1016/j.jelechem.2011.04.022

► First antioxidant biosensor measuring O 2 - radical induced DNA-damage. ► NADH catalyst arisen from electrooxidation of intact adenines allowed detection. ► The lower the damage, the higher the catalyst amount and electrocatalytic NADH current. ► O 2 - and OH damaging power compared in the presence of various antioxidants. ► CV experiments indicated that O 2 - and OH caused different lesions on DNA. The integrity of DNA purine bases was herein used to evaluate the antioxidant capacity. Unlike other DNA-based antioxidant sensors reported so far, the damaging agent chosen was the O 2 - radical enzymatically generated by the xanthine/xanthine oxidase system. An adenine-rich oligonucleotide was adsorbed on carbon paste electrodes and subjected to radical damage in the presence/absence of several antioxidant compounds. As a result, partial damage on DNA was observed. A minor product of the radical oxidation was identified by cyclic voltammetry as a diimine adenine derivative also formed during the electrochemical oxidation of adenine/guanine bases. The protective efficiency of several antioxidant compounds was evaluated after electrochemical oxidation of the remaining unoxidized adenine bases, by measuring the electrocatalytic current of NADH mediated by the adsorbed catalyst species generated. A comparison between O 2 - and OH radicals as a source of DNA lesions and the scavenging efficiency of various antioxidant compounds against both of them is discussed. Finally, the antioxidant capacity of beverages was evaluated and compared with the results obtained with an optical method.