In the present study, the effects of cerium （Ce） on the growth and physiological changes were investigated in the cyanobacterium Anabaena flosaquae （A. flosaquae） during a 17-day period. The results showed that th...In the present study, the effects of cerium （Ce） on the growth and physiological changes were investigated in the cyanobacterium Anabaena flosaquae （A. flosaquae） during a 17-day period. The results showed that the content of chlorophyll a （chl-a） and activity of antioxidase （e.g. superoxide dismutase, peroxidase, and catalase） increased with Ce3＋ concentration in the range of 0.05 to 0.1 mg/L and the growth ofA. flosaquae was stimulated. While at around 5 mg/L, the content of malondiadehyde （MDA） increased significantly but the activity of antioxidase reduced, which resulted in the ruin of antioxidant defense system. Compared to the control （Ce3＋-free）, the population size of live cells declined significantly. Microcystin-LR （MC-LR）, the most common and toxic cyanotoxins produced by A. flosaquae, was detected and the highest content of MC-LR was observed in 10 mg/L Ce3＋ treatment. These results implied that the aqueous environment might suffer a more negative ecological impact when exposed to relatively low Ce3＋ concentrations （〈0.1 mg/L）.展开更多
基金Project supported by the Major Project of Education Department in Sichuan (10ZA059)
文摘In the present study, the effects of cerium （Ce） on the growth and physiological changes were investigated in the cyanobacterium Anabaena flosaquae （A. flosaquae） during a 17-day period. The results showed that the content of chlorophyll a （chl-a） and activity of antioxidase （e.g. superoxide dismutase, peroxidase, and catalase） increased with Ce3＋ concentration in the range of 0.05 to 0.1 mg/L and the growth ofA. flosaquae was stimulated. While at around 5 mg/L, the content of malondiadehyde （MDA） increased significantly but the activity of antioxidase reduced, which resulted in the ruin of antioxidant defense system. Compared to the control （Ce3＋-free）, the population size of live cells declined significantly. Microcystin-LR （MC-LR）, the most common and toxic cyanotoxins produced by A. flosaquae, was detected and the highest content of MC-LR was observed in 10 mg/L Ce3＋ treatment. These results implied that the aqueous environment might suffer a more negative ecological impact when exposed to relatively low Ce3＋ concentrations （〈0.1 mg/L）.
