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Study of low temperature plasma direct application on yeasts Candida Glabrata and bacteries
Petrová, Veronika ; Kodedová,, Marie (referee) ; Krčma, František (advisor)
The subject of this thesis is to study the interactions of the low-temperature microwave plasma with selected microorganisms Candida glabrata, Staphylococcus epidermidis, and Escherichia coli and their combinations. The inhibitory effect of the plasma on these microorganisms is monitored on selected solid nutrient media and in suspension (nutrient medium and PBS). The inhibitory effect on the mixed cultures of these microorganisms is also studied on the solid nutrient media. The surface wave microwave discharge is used, with argon as a working gas. For the experiment on the solid nutrient media, a constant gas flow rate of 5,0 Slm and a power fluctuating between 8-10 W are maintained throughout the experiment. For the suspension experiment, a constant gas flow rate of 2,0 Slm and 13 W power are maintained throughout the experiment. The inhibitory effects of plasma on the solid nutrient media were observed on the individual microorganisms as well as on the mixed cultures. It was found that the microorganisms treated by plasma on the solid nutrient media were inhibited and uncultivable, while their cytoplasmic membrane remained intact. When the microorganisms were treated in suspension, individual cells were killed, but the efficiency was low. This was caused by the experimental setup, specifically due to the plasma only being formed in argon (no intermixing with air), as the capillary was submerged in the treated suspension.
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Application of plasma and plasma activated water in cosmetics
Kocianová, Magdaléna ; Tarabová,, Barbora (referee) ; Kozáková, Zdenka (advisor)
This diploma thesis is focused on the study of the inhibitory effects of the cold atmospheric pressure plasma on the grampositive, anaerobic, non-sporulating bacteria Propionibacterium acnes. The treatment was carried out by a direct application of plasma, indirectly (using plasma-treated liquids) and also in their combination. The plasma sterilization process is fast, effective, non-toxic, environmentally friendly, cost-effective and safe not only for the operating staff, but especially for the patient. The experimental part focuses on the study of the direct application of plasma. Two plasma devices for the generation of microwave plasma were used. One of them was a unipolar microwave discharge torch with direct gas supply and the other was a microwave discharge with a surface wave. Discharges were generated in argon with a flow rate of 5 Slm, at a power of 9 W and 12 W. The work also deals with the indirect treatment using plasma-treated liquids. These were prepared using the pinhole discharge and the dielectric barrier discharge. In the last part, combined treatment using plasma-treated liquid and direct plasma treatment was studied. From the achieved results, it can be concluded that the sterilization effects of the plasma and the plasma-treated liquids on the Propionibacterium acnes were confirmed.
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Alleopathic potential of plants of hemp (\kur{Cannabis sativa})
KLEJNA, Tomáš
The aim of the work was to compare the effects of germinating seeds, fresh flowers and aqueous extracts from fresh and dried parts (leaves and flowers) of hemp plants on seed germination of model crops - wheat, oats, white mustard, narrow-leaved lupin, white clover and lettuce in laboratory conditions. After 3 days of germination, the total length of the roots and shoots was measured. In individual variants, the relative allelopathic effect, average germination and statistical significance were evaluated. The effect of the distance of germinating seeds from samples of hemp material was also monitored. The effect of germinating hemp seeds, with the exception of oats, has not proved to be very significant. The effect of parts and aqueous extracts of hemp plants was as follows: -statistically significant inhibitory effect of the aqueous extract of the dried flower on the germination of wheat -statistically significant inhibitory effect of fresh flowers and extract from dried leaves of flowering plants on the germination of oats, there is also a statistically significant effect of the distance of germinating seeds from the sample of hemp material -statistically significant inhibitory effect of fresh flowers and extracts of fresh and dried leaves on the germination of white mustard, there is also an effect on average germination values -practically no or stimulating effect on the germination of legumes: narrow-leaved lupins and white clover -statistically significant inhibitory effect of fresh flowers and fresh leaf extract on lettuce germination, again with an effect on average germination
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