Combined effects of sucrose and copper(II) ions on the growth and copper(II) bioaccumulation properties of Candida sp

A microbiological process using Candida sp was developed for the removal of copper(II) ions in the presence of molasses as nutrient. The combined effe cts of sucrose (in molasses) and copper(II) ions on the growth and copper(I I) bioaccumulation properties of adapted Candida cells was tested under lab oratory conditions as a function of initial pH and single-sucrose and dual- sucrose and copper(II) ion concentrations. The optimum pH value for maximum growth and metal ion accumulation was determined as 4.0 for the microorgan ism. At a constant copper(II) concentration, growth and copper(II) bioaccum ulation increased with increasing concentrations of molasses sucrose up to 15 gdm(-3). Although increased initial copper(II) concentration increased t he copper(II) uptake capacity of the microorganism, inhibition by copper(II ) ions of the growth of Candida sp was observed at all the concentrations o f copper(II) at all the sucrose concentrations studied. The non-competitive inhibition kinetics (assuming copper(II) ions as the toxic inhibitory comp onent) were used to define the relationship between the specific growth rat e and molasses sucrose and copper(II) concentrations and model parameters w ere determined by using experimental data. (C) 2000 Society of Chemical Ind ustry.