Group biostatic/biocidic impact of yeast strain colonies secreting red pigments on Saccharomyces cerevisiae yeast

Abstract

We have determined the biostatic/biocidic impact of secreting non-identified substances of V2, V3, V4 yeast strain group colonies (cells) on S. cerevisiae yeast. We have proved that separate colonies do not produce such substances; the above property can only be identified in group of colonies. The effect grows with the increase of the density. The biocides area can be smaller or equal to the boundaries of pigment diffusion. The secreting pigments evidently interact with one another in a specific way: the diffusion zones are distorted, whereas the standart killer strains are secreting the substances equally to all directions. These phenomena can hardly be clarified without electrochemical analyses. Amperometric testing of redox activity in intact yeast cells by using carbon paste electrodes with immobilized yeast revealed more than five-fold higher current responses to glucose compared to those obtained with control killer S. cerevisiae. The conditions for the yeast culture have been optimised. The possibility of managing these processes have been offered depending on the composition of the medium. Excretive biocidical substances and their secreting can be related to the consumption of food substances in the medium: secreting is started while certain substances are lacking. Hypothetically, in such a case new genes should become active. The phenomena could be applied as a model in the analysis of the spread of diseases caused by microbes in eukaryotic organisms.