[Effect of chromium (VI) on growth physiology and sorptional capacity of yeast]

Abstract

Resistance of 7 yeast species (7 strains) to various chrome concentrations in the medium and their sorptional activity have been studied. It is shown that the biomass of the yeast Williopsis californica UKM-248, Candida krusei UKM-61t under their concentration in the medium of 200 and 500 mg/l of Cr6+ is 0.74 and 0.45 g/l DWB, respectively. For the rest of strains these chrome concentrations are toxical and the concentration of 100 mg/l of Cr6+ is the bordering threshold for them. Under periodical cultivation in the medium with 30 mg/l of Cr6+ one can observe the delay of cultures growth displayed in the increase of the lag-phase and exponential growth phase as well as the decrease of medium pH (to 2). The resistance of the studied yeast to high concentrations of Cr6+ correlates with their sorptional activity.