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.
College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, 250014 Jinan, China. tangb@sdnu.edu.cn
Bo
B
Tang
Yan
Y
Wang
Li
L
Ma
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