Surface Treatment of Materials for BioTechnologies

The theoretical part focuses on the importance of yeast, its role in brewing, the need for a reliable and economically beneficial pasteurization step that would meet modern requirements. Also in this part is defined plasma, its occurrence and the use of the glass structure used in the practical part. In the first part of the experimental work, the bachelor thesis deals with the action of plasma as a means of pasteurization. Saccharomyces cerevisiae yeast was introduced into the plasma. Gradually, the period of exposure of the yeast to the plasma discharge was determined and the number of survived and dead cells monitored. The methylene blue dye was used to identify yeast viability. After staining, the yeast was monitored under a microscope and calculated. Bürker's cell was used to determine the number of yeast cells. The experiment demonstrated plasma activity as a sterilization step, due to the decreasing number of living cells and the increase in the number of dead cells in the yeast-containing sample. In the 2nd part the surface was activated in the plasma discharge. The glass thus prepared was immersed in the culture medium for 24 hours to form a layer of culture medium on the surface of the glass. The remainders of the culture medium were then discharged and a small amount of yeast in the distilled water was pipetted. After 24 hours the yeast was counted on the Bürker's cell, the yeast growth was evaluated and the plasma activation efficiency was evaluated for activation and layer formation. The method of contact angles was used to confirm the effect of plasma on the surface of the glass. In this section, we demonstrated the effect of plasma on the surface of the glass and the formation of a thin layer of nutrient medium that supplied the yeast with the necessary substances for reproduction