Influence of environmental conditions on the dynamics of biofilm development by the phenol degrading yeast

摘要

The aim of this work was to examine the ability of Candida maltosa, a yeast utilizing phenol as sole carbon and energy sources, to form biofilm under different environmental conditions. The flow chamber with a synthetic foil (Steriking~(~R) R40) as a transparent carrier was chosen for the assessment of biofilm growth. On line image analysis system was used for the evaluation biomass distribution on the surfaces of synthetic foil. We have shown that the physiological state of C. maltosa population, the nutrient composition and the medium flow rate had significant influence on biofilm growth, especially in the first stadium this process. The nutrition richness of media for the C. maltosa inoculum production is important for the size of cell clusters, thickness or interstitial spaces in growth biofilm. The same effect was proved in direct dependence on the medium flow rate in the range from 3,0 to 90,0 ml.min~(-1). We have shown, furthermore, that the environmental conditions that stimulated production of extracellular substances in C. maltosa, improved biofilm growth parameters, too. In this context, an addition of 2,4-dinitrophenol, declared as an inhibitor of extracellular polysaccharides production in bacteria, into the flow medium caused considerable decrease of biofilm formation on a foil surface. In comparison with suspended yeast cells, the efficiency of phenol degradation by biofilm cells is enhanced as well. The shown results are indispensable for the following development of a powerful bioremediation technology based on C. maltosa biofilm.