INFLUENCE OF SOME POLLUTANTS ON YEASTS FERMENTATION CAPACITY

摘要

The paper presents the results of our comparative research on the influence of some heavy metals (Cd, Pb, Cu, Zn and Mn) on the fermentation capacity of the wine yeast Saccharomyces cerevisia var. ellipsoideus (sin. S. ellipsoideus). During the alcoholic fermentation we have examined the dynamics of the must fermentation due to the yeast, in the presence of these metals, measuring the amount of CO_2 produced in 24 hours, using current standard methods. The results have shown that the heavy metals have a differentiated toxic effect on the yeast fermentation dynamics of the must. The toxic effect can be correlated both to the specific action of each metal and to the metal amount in the fermentation medium. It can be determined a certain order of the toxicity degree of the studied metals on the fermentation dynamics of the must. Thus, the decreasing order of the toxicity degree of the studied metals is: Cd, Pb, Cu, Mn and Zn. The yeast Saccharomyces cerevisiae can be used as a bioindicator for the heavy metals existing in food.