SUBSTRATE-DEPENDENT BIOACCUMULATION OF CADMIUM BY GROWING YEAST CANDIDA-UTILIS

The ability of growing yeast Candida utilis to accumulate cadmium ions from the cultivation broth depends on the carbon source used; xylose and glucose were tested here. For the two substrates, the course of ca dmium bioaccumulation and total uptake were quite different. With gluc ose the maximum of bioaccumulation was about ten times higher than wit h xylose. The data were consistent with a simple mathematical model of process dynamics which assumes a Freundlich isotherm to describe the biosorption equilibrium and first-order dynamics to simulate the trans ient state.