title: Identification and antioxidant activity of several pigments from the residual green tea (Camellia sinensis) after hot water extraction.
abstract: Antioxidant activity of green tea extract or tea-derived polyphenols has been extensively studied. However, antioxidant activity in the non-polyphenolic fraction of green tea has been poorly analyzed. In the present study, we analyzed the antioxidant activity of the non-polyphenolic fraction of the residual green tea (Camellia sinensis) after hot water extraction using the aluminum chloride method. The non-polyphenolic fraction of residual green tea caused a significant suppression against hydroperoxide generation from oxidized linoleic acid in a dose-dependent manner. When the concentrate of the non-polyphenolic fraction was applied to a silica gel TLC plate and developed, six color spots were observed, which were considered to be chlorophylls a and b, pheophytins a and b, carotenoids, such as beta-carotene and lutein according to their specific colors, Rf values of silica gel TLC and spectrophotometric properties. Among these pigments, pheophytins a and b showed relatively abundant amounts, and the second major group of the pigment was chlorophylls a and b, and carotenoids such as beta-carotene and lutein indicated lower concentrations. Although all these pigments exhibited significant antioxidant activities, the ranks of suppressive activity against hydroperoxide generation were chlorophyll a > lutein > pheophytin a > chlorophyll b > beta-carotene > pheophytin b. These results suggest that the non-polyphenolic fraction of residual green tea has a potent suppressive activity against hydroperoxide generation from oxidized linoleic acid, which is derived from the antioxidant activities of chlorophylls a and b, pheophytins a and b, beta-carotene and lutein. This finding also implies that the combined intake of polyphenols in water-soluble fraction and antioxidative pigments in the non-polyphenolic fraction of green tea will be more efficient to prevent life style-related chronic diseases.
authors.affiliation: Department of Food and Nutrition, Hiroshima Jhogakuin University, Higashi-Ku, Hiroshima 732-0063, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Higashi-Okai
authors.forename: M
authors.initials: M
authors.lastname: Yamazaki
authors.forename: H
authors.initials: H
authors.lastname: Nagamori
authors.forename: Y
authors.initials: Y
authors.lastname: Okai
mesh_terms: D000096:Acetone; D000975:Antioxidants / Q000302:isolation & purification* / Q000494:pharmacology*; D028241:Camellia sinensis / Q000737:chemistry*; D002734:Chlorophyll / Q000302:isolation & purification / Q000494:pharmacology; D000077194:Chlorophyll A; D004305:Dose-Response Relationship, Drug; D006358:Hot Temperature; D008054:Lipid Peroxides / Q000037:antagonists & inhibitors; D014975:Lutein / Q000302:isolation & purification / Q000494:pharmacology; D010674:Pheophytins / Q000302:isolation & purification / Q000494:pharmacology; D010860:Pigments, Biological / Q000302:isolation & purification* / Q000494:pharmacology*; D013662:Tea / Q000737:chemistry*; D014867:Water; D019207:beta Carotene / Q000302:isolation & purification / Q000494:pharmacology
chemical_list: D000975:Antioxidants; D008054:Lipid Peroxides; D010674:Pheophytins; D010860:Pigments, Biological; D013662:Tea; D019207:beta Carotene; D014867:Water; D000096:Acetone; D002734:Chlorophyll; C037184:chlorophyll b; D014975:Lutein; D000077194:Chlorophyll A