title: [Antioxidant activities of green and black teas determined by the cumene hydroperoxide/hemoglobin.methylene blue method].
abstract: Antioxidant activity in tea was measured by the new cumene hydroperoxide/hemoglobin.methylene blue(CHP/Hb.MB) method developed in our laboratory. Using the CHP/Hb.MB method, we investigated the activities of polyphenols(11 varieties) in order to determine their reactivity on CHP. According to the CHP/Hb.MB method, an increase in the number of hydroxyl groups in polyphenols induced high antioxidant activity. We found that this method was capable of measuring the antioxidant activity of polyphenols. Consequently, we were able to measure the antioxidant activities of heated, green, powdered and black teas by this method. The average of antioxidant activities of heated green tea was 207 nmol/ml, while that of green tea was 280 nmol/ml, powdered green tea was 481 nmol/ml and black tea was 215 nmol/ml respectively.
authors.affiliation: Niigata College of Nursing, Joetsu 943-0147.
authors.forename: Osamu
authors.initials: O
authors.lastname: Sugita
authors.forename: Nobuhito
authors.initials: N
authors.lastname: Ishizawa
authors.forename: Masaharu
authors.initials: M
authors.lastname: Nakano
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsuto
authors.forename: Masahiko
authors.initials: M
authors.lastname: Okada
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D001555:Benzene Derivatives; D005419:Flavonoids; D006454:Hemoglobins; D008751:Methylene Blue; D010636:Phenols / Q000494:pharmacology*; D011108:Polymers / Q000494:pharmacology*; D059808:Polyphenols; D013662:Tea / Q000737:chemistry*
chemical_list: D000975:Antioxidants; D001555:Benzene Derivatives; D005419:Flavonoids; D006454:Hemoglobins; D010636:Phenols; D011108:Polymers; D059808:Polyphenols; D013662:Tea; C007164:cumene hydroperoxide; D008751:Methylene Blue