Chen Jian, Shiyab Safwan, Han Fengxiang X, Monts David L, Waggoner Charles A, Yang Zhimin, Su Yi
Department of Biochemistry & Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
Ecotoxicology. 2009 Jan;18(1):110-21. doi: 10.1007/s10646-008-0264-3. Epub 2008 Sep 3.
Anatomical, histochemical and biochemical approaches were used to study mercury uptake and phytotoxicity as well as anti-oxidative responses in two species of ferns [Chinese brake fern (Pteris vittata) and Boston fern (Nephrolepis exaltata)], grown in a hydroponic system. The roots of both cultivars accumulated large amounts of mercury, but exhibited limited mercury translocation to shoots. Mercury exposure led to more pronounced phytotoxicity accompanied by stronger oxidative stress in the shoots of P. vittata than in N. exaltata. N. exaltata established a more effective anti-oxidative system against mercury-induced oxidative stress than did P. vittata. The activity of anti-oxidative enzymes (superoxide dismutase, catalase and glutathione reductase) increased. The reduced ascorbate (ASA) and oxidized ascorbate (DHA) are regulated. Mercury exposure led to an increase in the concentration of glutathione (GSH) in both fern species. The present study suggests that N. exaltata is more tolerant to mercury exposure than P. vittata, which has been also reported to be more tolerant to arsenic exposure. N. exaltata may thus have potential for phytostabilization of soils or phytofiltration of waste water contaminated with mercury.
采用解剖学、组织化学和生物化学方法，研究了水培系统中生长的两种蕨类植物[蜈蚣草（Pteris vittata）和波士顿蕨（Nephrolepis exaltata）]对汞的吸收、植物毒性以及抗氧化反应。两个品种的根系都积累了大量汞，但向地上部的汞转运有限。汞暴露导致蜈蚣草地上部比波士顿蕨表现出更明显的植物毒性，同时伴随着更强的氧化应激。与蜈蚣草相比，波士顿蕨建立了更有效的抗氧化系统来抵御汞诱导的氧化应激。抗氧化酶（超氧化物歧化酶、过氧化氢酶和谷胱甘肽还原酶）的活性增加。还原型抗坏血酸（ASA）和氧化型抗坏血酸（DHA）受到调控。汞暴露导致两种蕨类植物中谷胱甘肽（GSH）浓度增加。本研究表明，波士顿蕨比蜈蚣草更耐汞暴露，此前也有报道称蜈蚣草更耐砷暴露。因此，波士顿蕨可能具有对汞污染土壤进行植物稳定或对废水进行植物过滤的潜力。
