title: Purification and in vitro antioxidant activities of tellurium-containing phycobiliproteins from tellurium-enriched Spirulina platensis.
abstract: Tellurium-containing phycocyanin (Te-PC) and allophycocyanin (Te-APC), two organic tellurium (Te) species, were purified from tellurium-enriched Spirulina platensis by a fast protein liquid chromatographic method. It was found that the incorporation of Te into the peptides enhanced the antioxidant activities of both phycobiliproteins. With fractionation by ammonium sulfate precipitation and hydroxylapatite chromatography, Te-PC and Te-APC could be effectively separated with high purity, and Te concentrations were 611.1 and 625.3 μg g(-1) protein in Te-PC and Te-APC, respectively. The subunits in the proteins were identified by using MALDI-TOF-TOF mass spectrometry. Te incorporation enhanced the antioxidant activities of both phycobiliproteins, as examined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, Te-PC and Te-APC showed dose-dependent protection on erythrocytes against the water-soluble free radical initiator 2,2'-azo(2-asmidinopropane)dihydrochloride-induced hemolysis. In the hepatoprotective model, apoptotic cell death and nuclear condensation induced by tert-butyl hydroperoxide in HepG2 cells was significantly attenuated by Te-PC and Te-APC. Taken together, these results suggest that Te-PC and Te-APC are promising Te-containing proteins with application potential for treatment of diseases related to oxidative stress.
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Fang
authors.initials: F
authors.lastname: Yang
authors.affiliation: Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong, People's Republic of China.
authors.forename: Ka-Hing
authors.initials: KH
authors.lastname: Wong
authors.affiliation: Institute of Hydrobiology, College of Life Science and Technology, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Yufeng
authors.initials: Y
authors.lastname: Yang
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Jiang
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Zheng
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Hualian
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Chemistry, Jinan University, Guangzhou, People's Republic of China.
authors.forename: Tianfeng
authors.initials: T
authors.lastname: Chen
mesh_terms: D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016923:Cell Death / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D056945:Hep G2 Cells; D006801:Humans; D013058:Mass Spectrometry; D009942:Organometallic Compounds / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D010798:Phycocyanin / Q000737:chemistry* / Q000302:isolation & purification; D013056:Spectrophotometry, Ultraviolet; D053545:Spirulina / Q000737:chemistry*; D013329:Structure-Activity Relationship; D013691:Tellurium / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D000975:Antioxidants; D009942:Organometallic Compounds; C002497:allophycocyanin; D010798:Phycocyanin; D013691:Tellurium
keywords: allophycocyanin; antioxidant activity; phycocyanin; purification; tellurium