The role of EDTA in malonaldehyde formation from DNA oxidized by Fenton reagent systems.
Calf thymus DNA was oxidized by various Fenton reagent systems [Fe(II)/H(2)O(2)] with or without ethylenediamine tetraacetic acid (EDTA) under different reaction conditions. Calf DNA was also oxidized by a modified Fenton reagent (Fe(III)/H(2)O(2)/ascorbic acid) with EDTA. Malonaldehyde (MA) formed from DNA was derivatized into 1-methyl hydrazine, which was subsequently analyzed by gas chromatography with a nitrogen-phosphorus detector. MA formation increased linearly with an increase of Fe(II) concentration. MA formation reached a plateau at nearly 2 mmol/L of Fe(II) with 0.5 mmol/L of H(2)O(2). Addition of EDTA increased MA formation from DNA nearly 5 times. When DNA was oxidized with various amount of ethanol, MA formation decreased with an increase of ethanol concentration, either with or without EDTA. The rate of inhibition was greater without EDTA than with EDTA. When DNA was oxidized by a modified Fenton reagent, MA formation linearly increased with the increase of DNA. Ascorbic acid alone produced some MA upon oxidation.
Matsufuji
Hiroshi
H
Department of Environmental Toxicology, University of California, Davis, One Shields Avenue, Davis, California 95616, USA.
Shibamoto
Takayuki
T
D000818:Animals; D002417:Cattle; D004247:DNA / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry*; D006861:Hydrogen Peroxide; D007501:Iron; D007700:Kinetics; D008315:Malondialdehyde / Q000737:chemistry*; D010084:Oxidation-Reduction; D013950:Thymus Gland / Q000737:chemistry
C045076:Fenton's reagent; D008315:Malondialdehyde; D004247:DNA; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D007501:Iron