Effects of selenium on biological and physiological properties of the duckweed Landoltia punctata.
Duckweed can be used for bioremediation of selenium (Se) polluted water because of its capability of absorbing minerals from growing media. However, the presence of Se in the media may affect the growth of the duckweed. Landoltia punctata 7449 has been studied for its changes in chemical and biological properties with the presence of Se in the media. The duckweed was cultivated over a 12-day period at different initial concentrations of selenite (Na2 SeO3 ) from 0 to 80 μmol·l(-1) . The growth rate, the organic and total Se contents, the activity of antioxidant enzymes, the photosynthetic pigment contents, the chlorophyll a fluorescence OJIP transient, and the ultrastructure of the duckweed were monitored during the experiment. The results have shown that Se at low concentrations of ≤20 μmol·l(-1) promoted the growth of the L. punctata and inhibited lipid peroxidation. Substantial increases in duckweed growth rate and organic Se content in the duckweed were observed at low Se concentrations. The anti-oxidative effect occurred likely with the increases in guaiacol peroxidase, catalase and superoxide dismutase activities as well as the amount of photosynthetic pigments. However, negative impact to the duckweed was observed when the L. punctata was exposed to high Se concentrations (≥40 μmol·l(-1) ), in which the duckweed growth was inhibited by the selenium. The results indicate that L. punctata 7449 can be used for bioremediation of selenium (Se) polluted water when the Se concentration is ≤20 μmol·l(-1) .
School of Environment and Energy, Peking University-Shenzhen Graduate School, Shenzhen, China.
Y
Y
Zhong
School of Environment and Energy, Peking University-Shenzhen Graduate School, Shenzhen, China.|Department of Biological and Agricultural Engineering, North Carolina State University, Raleigh, NC, USA.
J J
JJ
Cheng
D000975:Antioxidants / Q000494:pharmacology; D029064:Araceae / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D001673:Biodegradation, Environmental; D002374:Catalase / Q000187:drug effects / Q000378:metabolism; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D002736:Chloroplasts / Q000648:ultrastructure; D015227:Lipid Peroxidation / Q000187:drug effects; D008928:Mitochondria / Q000648:ultrastructure; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000187:drug effects / Q000378:metabolism; D010788:Photosynthesis / Q000187:drug effects* / Q000502:physiology; D020887:Selenious Acid / Q000378:metabolism / Q000494:pharmacology; D012643:Selenium / Q000378:metabolism / Q000494:pharmacology*; D013482:Superoxide Dismutase / Q000187:drug effects / Q000378:metabolism
D000975:Antioxidants; D002734:Chlorophyll; C121048:guaiacol peroxidase; D002374:Catalase; D009195:Peroxidase; D013482:Superoxide Dismutase; D020887:Selenious Acid; D012643:Selenium; D000077194:Chlorophyll A
Antioxidant enzymes; Landoltia punctata; photosynthetic pigments; selenium