The objective of this research is to demonstrate the antioxdant ecological response of
Vallisneria asiatica to the heavy metal Cu
2+ pollution which is recently a serious problem in the lakes. Batch experiments with five different concentrations of Cu
2+ (0, 5, 10, 20, 40, 80 mg· L
-1) were carried out. After the 12
th day, the roots and leaves of
Vallisneria asiatica dipped in the solution with Cu
2+ were removed and the physiological and biochemical indexes, chlorophyll, protein and malondialdehyde (MDA) content, superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) activity were measured. After the experiment; the roots and leaves cultivated in the 0 mg·L
-1 of Cu
2+ group showed chlorophyll and protein content reduced while the MDA content, POD and SOD activity were increased notoriously. Compared with the 0 mg·L
-1 of Cu
2+ group, the 5 mg·L
-1 of Cu
2+ group showed chlorophyll and protein content increase, SOD and POD activity showed also a slight increase, while MDA content decreased. However, for the 10 mg·L
-1 of Cu
2+ group, the decrease of chlorophyll and protein content and the increase of MDA content were observed. Also a sharp increase of SOD and CAT activity compared with the 5 mg·L
-1 group were found; for over 10 mg·L
-1 of Cu
2+ concentration, chlorophyll content and protein content fell off, whereas increase of MDA became considerable, CAT raised up steadily and POD showed a decrease trend. The results showed that, both insufficiency and overabundance of Cu
2+ in water environment can affect the anti-oxidation function of
Vallisneria asiatica which can be observed by the value of SOD, CAT and POD activity. Therefore, the measurement of anti-oxidation activity, protein content and MDA as a forecast and judgment indicator of Cu
2+ contaminations in the water environment can be considered in the future.
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