title: Novel high-throughput assay for antioxidant capacity against superoxide anion.
abstract: A novel high-throughput assay for measuring antioxidant capacity against superoxide anion has been developed and validated. In this assay, hydroethidine (HE), a fluorescent probe, is oxidized by superoxide anion generated by xanthine and xanthine oxidase and increases its fluorescence intensity. Therefore, the inhibition of loss of HE's fluorescence intensity in the presence of antioxidant is an index of antioxidant capacity. The result is expressed as superoxide dismutase (SOD) equivalent. Unlike other probes, such as tetrazolium and lucigenin, one major advantage of this assay is that the use of HE is not prone to artifact. The method was rigorously validated through linearity, precision, accuracy, and ruggedness. The linear range, limit of quantitation (LOQ), and limit of detection (LOD) are 0.22-3.75 units/mL, 0.30 unit/mL, and 0.10 unit/mL, respectively. A wide variety of phenolic compounds and fruit extracts were analyzed.
authors.affiliation: Brunswick Laboratories, Norton, Massachusetts 02766, USA.
authors.forename: Liliang
authors.initials: L
authors.lastname: Zhang
authors.forename: Dejian
authors.initials: D
authors.lastname: Huang
authors.forename: Miwako
authors.initials: M
authors.lastname: Kondo
authors.forename: Ellen
authors.initials: E
authors.lastname: Fan
authors.forename: Hongping
authors.initials: H
authors.lastname: Ji
authors.forename: Yan
authors.initials: Y
authors.lastname: Kou
authors.forename: Boxin
authors.initials: B
authors.lastname: Ou
mesh_terms: D000975:Antioxidants / Q000032:analysis / Q000737:chemistry*; D005456:Fluorescent Dyes; D005638:Fruit / Q000737:chemistry; D010084:Oxidation-Reduction; D010617:Phenanthridines / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry; D012680:Sensitivity and Specificity; D013482:Superoxide Dismutase / Q000378:metabolism; D013481:Superoxides / Q000737:chemistry* / Q000378:metabolism; D019820:Xanthine / Q000378:metabolism; D014969:Xanthine Oxidase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005456:Fluorescent Dyes; D010617:Phenanthridines; D010636:Phenols; D010936:Plant Extracts; D013481:Superoxides; D019820:Xanthine; C058428:hydroethidine; D013482:Superoxide Dismutase; D014969:Xanthine Oxidase