摘要
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）.
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）.
基金
Project supported by the Major Project of Education Department in Sichuan (10ZA059)
