title: Comparative evaluation of the radical-scavenging activities of fucoxanthin and its stereoisomers.
abstract: Fucoxanthin (Fuco) is a characteristic carotenoid of brown seaweeds. In the present study, Fuco and its stereoisomers 9'Z-Fuco, 13Z- and 13'Z-Fuco were extracted from Laminaria japonica Aresch. They were isolated and purified by silica gel column chromatography, Sephadex LH-20, and reversed-phase HPLC. The radical-scavenging activities of the three stereoisomers were evaluated toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, 2-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical, hydroxyl radical, and superoxide radical. The order of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity was 13Z- and 13'Z-Fuco > (all-E)-Fuco > 9'Z-Fuco. The order of 2-2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and hydroxyl radical-scavenging activities were 9'Z-Fuco > (all-E)-Fuco > 13Z-and 13'Z-Fuco. The order of superoxide radical-scavenging activity was 13Z- and 13'Z-Fuco > (all-E)-Fuco > 9'Z-Fuco. The scavenging activities of Fuco and its stereoisomers toward the four radical types were all dose-dependent. The ABTS, DPPH, and superoxide radical-scavenging activities were all weaker than that of tocopherol (VE), while their hydroxyl radical-scavenging activities were stronger than that of VE. The results confirmed that Fuco and its stereoisomers have potent antioxidant activities.
authors.affiliation: Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu, China. zhangyiping310@163.com.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Oceanic Administration Third Institute of Oceanography, Xiamen 361005, Fujian, China. fangh6115@163.com.
authors.forename: Hua
authors.initials: H
authors.lastname: Fang
authors.affiliation: State Oceanic Administration Third Institute of Oceanography, Xiamen 361005, Fujian, China. XieQuanling@163.com.
authors.forename: Quanling
authors.initials: Q
authors.lastname: Xie
authors.affiliation: State Oceanic Administration Third Institute of Oceanography, Xiamen 361005, Fujian, China. sunjipeng80@163.com.
authors.forename: Jipeng
authors.initials: J
authors.lastname: Sun
authors.affiliation: Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu, China. cpulr@126.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: State Oceanic Administration Third Institute of Oceanography, Xiamen 361005, Fujian, China. xm_hzh@163.com.
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Hong
authors.affiliation: State Oceanic Administration Third Institute of Oceanography, Xiamen 361005, Fujian, China. yiruizao@163.com.
authors.forename: Ruizao
authors.initials: R
authors.lastname: Yi
authors.affiliation: Nanjing University of Chinese Medicine, Nanjing 210023, Jiangsu, China. whao5795@vip.sina.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
mesh_terms: D002338:Carotenoids / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D012624:Seaweed / Q000737:chemistry; D013237:Stereoisomerism; D013451:Sulfonic Acids / Q000737:chemistry; D024341:Xanthophylls / Q000737:chemistry / Q000302:isolation & purification*
chemical_list: D016166:Free Radical Scavengers; D013451:Sulfonic Acids; D024341:Xanthophylls; C025164:fucoxanthin; D017665:Hydroxyl Radical; D002338:Carotenoids