title: Development of singlet oxygen absorption capacity (SOAC) assay method. 4. Measurements of the SOAC values for vegetable and fruit extracts.
abstract: Measurements of the second-order rate constants and the singlet oxygen absorption capacity (SOAC) values for the reaction of singlet oxygen ((1)O2) with 23 kinds of food extracts were performed in ethanol/chloroform/D2O (50:50:1, v/v/v) solution at 35 °C. It has been clarified that the SOAC method is useful to evaluate the (1)O2-quenching activity (i.e. the SOAC value) of food extracts having two orders of magnitude different rate constants from 3.18 × 10(4) L g(-1) s(-1) for tomato to 1.55 × 10(2) for green melon. Furthermore, comparison of the observed rate constants for the above food extracts with the calculated ones based on the concentrations of seven kinds of carotenoids included in the food extracts and the rate constants reported for each carotenoids was performed, in order to ascertain the validity of the SOAC assay method developed and to clarify the ratio of the contribution of principal carotenoids to the SOAC value.
authors.affiliation: a Research & Development Division , Kagome Co. Ltd. , Nasushiobara-shi , Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Iwasaki
authors.forename: Shingo
authors.initials: S
authors.lastname: Takahashi
authors.forename: Koichi
authors.initials: K
authors.lastname: Aizawa
authors.forename: Kazuo
authors.initials: K
authors.lastname: Mukai
mesh_terms: D065966:Absorption, Physicochemical; D005638:Fruit / Q000737:chemistry*; D007700:Kinetics; D010936:Plant Extracts / Q000737:chemistry*; D026082:Singlet Oxygen / Q000737:chemistry*; D014675:Vegetables / Q000737:chemistry*
chemical_list: D010936:Plant Extracts; D026082:Singlet Oxygen
keywords: SOAC value; carotenoids; food extracts; quenching rate; singlet oxygen