Effects of Heavy Metals (Copper, Cobalt and Lead) on the Growth and Photosynthetic pigments of the Green Alga Chlorella pyrenoidosa H. Chick

Document Type : Original Article

Author

Department of Botany and Microbiology, Faculty of Science, Alexandria University, Egypt

Abstract

The present study was carried out to investigate the effect of different concentrations (0.05, 0.5, 1, 2, 4, 6 and 8 mg/L) of Copper Cu2+, Cobalt Co2+ and Lead Pb2+ on growth, pigment contents, protein and antioxidant enzyme activities of superoxide dismutase (SOD) and catalase (CAT). The data show that the lower doses of Co2+ had stimulatory effect on biomass of Chlorella pyrenoidosa, whereas the higher doses were inhibitory depending on the type of the metals. The inhibitory effect of copper to growth parameters of Chlorella pyrenoidosa was more pronounced than other two tested metals. The total protein content of the tested green alga gradually decreased in a manner dependent on the metal concentration in the medium. Our results showed reduction in the antioxidant enzymes (SOD) and (CAT) in Chlorella pyrenoidosa after exposure when compared with activities in the control. The inhibitory effects of either of the used heavy metals depend on concentration and time of exposure. These results provide some additional information that can lead to better understand consequences of heavy metal poisoning in microalgae.

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