The purpose of the research was to estimate the influence of lactic acid bacteria on pathogenic bacteria of Salmonella Senftenberg W775. The method of co-cultures was applied in order to examine the interaction between the investigated microorganisms. The results obtained indicate that 3 LAB strains (numbers 2, 3, 4) isolated from fermented plant material indicated high antibacterial activity against Salmonella rods. The growth of the pathogen in associated cultures was completely inhibited in 48 hours. The theoretical survival of Salmonella incubated in the presence of Lactobacillus plantarum was significantly longer and amounted to 132 hours. None of the LAB strains examined was influenced by Salmonella rods.
Interaction between T. vaginalis and P. aeruginosa was studied in vitro. Protozoan cells were incubated in 0,9% NaCl at 37°C for 30 and 150 min. with bacteria, alive or killed by heating for 10 min. at 100°C. Transmission electron microscope observations showed weak fagocytic activity (<10%) of T. vaginalis against living P. aeruginosa. Phagocytosis of these bacteria caused death of T. vaginalis. Desintegration and autolysis of T. vaginalis resulted probably from action of exotoxin A produced by P. aeruginosa. Phagocytosis of dead P. aeruginosa has not been observed.