title: Micro-distribution of arsenic species in tissues of hyperaccumulator Pteris vittata L.
abstract: Arsenic (As) contamination and its harmful consequences have gained increasing attention in research. Phytoextraction, which uses the As hyperaccumulator Pteris vittata L., is a well-established technology adopted in many countries. However, the hyperaccumulation mechanisms of this plant remain controversial. This study investigated the species and the micro-distribution of As species in three P. vittata L. ecotypes after exposure to arsenite (AsIII) and arsenate (AsV) for 7d. Arsenic-accumulating abilities and preferences to As species varied among different ecotypes. The reduction of AsV into AsIII, oxidation of AsIII into AsV, and chelation of AsIII with thiols were all observed in P. vittata. The reduction of As mainly occurred in the rhizoid, whereas oxidation and chelation mainly occurred in the aboveground parts. Correlation analyses showed that the As concentration in pinna was significantly correlated with the AsV percentage in paraxial and abaxial epidermis (positive), AsIII-GSH percentage in paraxial epidermis (positive), and AsIII percentage in paraxial and abaxial epidermis (negative). Results indicated that oxidation and chelation reactions contributed to the accumulation of As in P. vittata.
authors.affiliation: Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Wan
authors.affiliation: Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China. Electronic address: leim@igsnrr.ac.cn.
authors.forename: Mei
authors.initials: M
authors.lastname: Lei
authors.affiliation: Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Tongbin
authors.initials: T
authors.lastname: Chen
authors.affiliation: School of Water Resources and Environment, China University of Geosciences, Beijing 100083, PR China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, PR China.
authors.forename: Jie
authors.initials: J
authors.lastname: Ma
mesh_terms: D001149:Arsenates / Q000493:pharmacokinetics*; D001673:Biodegradation, Environmental; D010084:Oxidation-Reduction; D032495:Pteris / Q000378:metabolism*; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D001149:Arsenates; D012989:Soil Pollutants
keywords: Arsenic species; Micro-distribution; Oxidation; Pteris vittata; Reduction; Thiol