title: Development of Singlet Oxygen Absorption Capacity (SOAC) Assay Method Using a Microplate Reader.
abstract: Recently, a new assay method that can quantify the singlet oxygen absorption capacity (SOAC) of natural antioxidants and food extracts was developed. The SOAC values were measured in ethanol-chloroform-D2O (50 + 50 + 1, v/v/v) solution at 35°C using a UV-Vis spectrophotometer equipped with a six-channel cell positioner and an electron-temperature control unit. In the present study, measurement of the SOAC values was performed for eight representative carotenoids and three vegetable extracts (tomato, carrot, and red paprika) using a versatile instrument, the microplate reader. A 24-well glass microplate was used for measurements because a plastic microplate, commonly used in the laboratory, dissolves in the ethanol-chloroform-D2O solution. The SOAC values of eight carotenoids and three vegetable extracts measured using a microplate reader were in good agreement with the corresponding values measured using a UV-Vis spectrophotometer, suggesting that the microplate reader is an applicable instrument for the measurement of reliable SOAC values for general antioxidants and food extracts in solution.
authors.affiliation: Kagome Co., Ltd, Research & Development Division, Nasushiobara, Tochigi 329-2762, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Takahashi
authors.forename: Yuko
authors.initials: Y
authors.lastname: Iwasaki-Kino
authors.forename: Koichi
authors.initials: K
authors.lastname: Aizawa
authors.forename: Junji
authors.initials: J
authors.lastname: Terao
authors.forename: Kazuo
authors.initials: K
authors.lastname: Mukai
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D010936:Plant Extracts / Q000032:analysis*; D026082:Singlet Oxygen / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000975:Antioxidants; D010936:Plant Extracts; D026082:Singlet Oxygen