RESUMO
The highest amount of zinc (approximately 90%) is bound after 3 h of contact at low initial (total) concentrations of zinc in yeast broth, 2.0-16.0 g/l at 10-30 degrees C. The equilibrium between bound and free zinc ions is established after 6 h of contact time, independently on total zinc concentration in yeast milk. No bigger changes of content of zinc bound to yeast cells was determined at 10 degrees C and 30 degrees C. 40% of bound zinc in the equilibrium state is bound during the first 15 min of contact of zinc ions and yeast cells at all initial (total) zinc concentrations in yeast milk both at 10 degrees C and 30 degrees C. The KEKAM (Kolmogorov-Erofeev-Kozeeva-Avrami-Mampel) equation can be used for the description of kinetics of zinc biosorption by yeast cells, for the ranges of zinc concentration of 2.0-16.0 g/l at 30 degrees C (mean correlation coefficient 0.96) and 10.0-16.0 g/l at 10 degrees C (mean correlation coefficient 0.95).
