Response of Tolerant and Wild Strains of Scenedesmus Biguja to Copper

Abstract

Copper tolerance in Scenedesmus biguja was studied by comparing the physiological properties and Cu uptake in wild type and copper tolerant strain. A concentration dependent reduction in growth rate, pigment, protein, sugar, and amino acid contents, oxygen evolution, and alkaline phosphatase activities was noticed in both strains at 1 and 200 μg(Cu) dm−3. The reduction in all parameters was higher in the wild type than in the tolerant strain. The tolerant strain showed also enhanced alkaline phosphatase activity, and insignificant loss of potassium and sodium. The Cu uptake was influenced by the Cu concentrations the algae had been exposed to during their previous growth: the lower the Cu concentration in the culture medium, the higher the activity of the uptake and the capacity of the cells to accumulate Cu.