Abstrakt

Bioaccumulation of Zinc (II) Ions by Candida Krusei Growing in Sugarcane Bagasse Extract

Saravanan P and Sathish Kumar S

Bioaccumulation of zinc (II) by yeast isolate C. krusei was investigated in different growth media. The isolate showed maximum bioaccumulation of zinc (II) in the medium prepared from sugarcane bagasse extract. The growth and bioaccumulation properties of yeast were tested as a function of pH and initial metal concentration in bagasse extract. The optimum pH value for growth and metal accumulation was determined as 5.5. The combined effects of sugar extracted from bagasse and initial zinc (II) concentration on specific growth rate and bioaccumulation efficiency of yeast was investigated. At a constant zinc (II) concentration, the growth and zinc (II) bioaccumulation increased with increasing concentrations of sugar up to 20 g/L. The inhibition effect of zinc (II) ions on the specific growth rate of yeasts was studied by non competitive and uncompetitive inhibition models at various concentrations of zinc (II) ranging from 0-25 mg/L at constant sugar concentrations (5- 20 g/L).