Simple and rapid catalytic spectrophotometric determination of superoxide anion radical and superoxide dismutase activity in natural medical vegetables using phenol as the substrate for horseradish peroxidase.
The coupling reaction of 4-aminoantipyrine (4-AAP) with phenol using the superoxide anion radical (O2-*) as oxidizing agent under the catalysis of horseradish peroxidase (HRP) was studied. Based on the reaction, O2-* produced by irradiating vitamin B2 (VB2) was spectrophotometrically determined at 510 nm. Under the optimum experimental conditions, the relationship between A510 and O2-* concentration was linear in the range 9.14x10(-6)-1.2x10(-4) mol L(-1). The detection limit was determined to be 1.37x10(-6) mol L(-1). A possible reaction mechanism was discussed. The effect of interferences and surfactants on the determination of O2-* was also investigated. The proposed method was applied to determine superoxide dismutase activity in garlic, scallion, and onion with satisfactory results.
Tang
Bo
B
College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, 250014 Jinan, China. tangb@sdnu.edu.cn
Wang
Yan
Y
Ma
Li
L
D002384:Catalysis; D004126:Dimethylformamide / Q000737:chemistry; D005737:Garlic / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000378:metabolism*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D019697:Onions / Q000737:chemistry; D019800:Phenol / Q000378:metabolism*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013056:Spectrophotometry, Ultraviolet; D013425:Sulfanilic Acids / Q000737:chemistry; D013482:Superoxide Dismutase / Q000032:analysis* / Q000378:metabolism; D013481:Superoxides / Q000032:analysis* / Q000378:metabolism; D014675:Vegetables / Q000737:chemistry*
D013425:Sulfanilic Acids; D013481:Superoxides; D019800:Phenol; D004126:Dimethylformamide; D006735:Horseradish Peroxidase; D013482:Superoxide Dismutase