| Abstract [eng] |
The Influence of Pulsed Electric Field Treatment on Specific Interaction Between Chorella vulgaris and Delftia sp. Bacteria Microalgae is a model microorganism distinguished by its high productivity and its high-value synthesized compounds, which are becoming more and more significant to biotechnology, food, pharmaceutical and energy industry sectors. To meet the rising demand and the accessibility for microalgae and its synthesized valuable compounds, optimization of its cultivation process is essential. The use of microorganisms with positive affect can be one of the most effective ways of reducing the cost and improving the growth rate of microalgae. It is known that interspecific interactions can be modulated by alteration of biotic and abiotic cultivation conditions. However, the influence of pulsed electric field to interspecific interactions has not been examined yet. Therefore, in order to examine the changes of interspecific interactions under the influence of pulsed-electric-field treatment, Chlorella vulgaris microalgae and Delftia sp. bacteria were selected. In the first stage of the research, when co-cultivating the above mentioned microorganisms, it was determined that the presence of Delftia sp. bacteria positively affected the growth rate of C. vulgaris biomass. In the second stage, the influence of pulsed-electric-field treatment on microorganism viability individually was determined. Based on the outcome of the experiment, a radical decrease of Delftia sp. viability is registered. Meanwhile, C. vulgaris viability remained undamaged. In the third stage of the research – Chlorella vulgaris and Delftia sp. were cultivated in photobioreactors. Most relevant changes of algae biomass were detected after exposure to electric field pulse E = 10 kV/cm, τ = 10 µs which likely indicate selective reduction of the viability in Delftia sp. bacteria. Therefore, the reduction in bacteria with a positive effect, determined the lower growth rate of C. vulgaris algae biomass, other than co-cultivation of microalgae and Delftia sp. not under the influence of an electric field. |
