Determination of in vitro effect of different substances to biofilm formation in some bacterial fish pathogens

In this study, adhesion formation and biofilm formation in bacterial fish pathogens Staphylococcus warneri, Aeromonas sobria, Yersinia ruckeri, Flavobacterium psychrophilum, Vibrio anguillarum were investigated. In addition to these strains, biofilm formation was investigated with lysozyme, malic acid, garlic oil, thyme oil on biofilm inhibition tests and different materials such as wood, metal, fiberglass and glass. In the adhesion test, when the one-hour attachment was 0.036 in the negative control, 0.044 in the V. anguillarum, 0.056 in the A. sobria, 0.040 in the S. warneri, 0.050 in the Y. ruckeri, and 0.059 in the F. psychrophilum formed the adhesion with the absorbance values. Adhesion strength F. psychrophilum was found to be much stronger than other pathogens. Adhesion test according to the absorbance values on the surface strength of the adhesion F. psychrophilum, A. sobria, Y. ruckeri, V. anguillarum, S. warneri was determined, respectively. In the tube method used for biofilm formation detection as F. psychrophilum (++), A. sobria (++), S. warneri (+), Y. ruckeri (-), V. anguillarum (-). In the tube test, F. psychrophilum, A. sobria, S. warneri, Y. ruckeri, V. anguillarum were determined according to the thickness of the film layer formed on the inner surface of the tube. The most potent biofilm formation was observed in F. psychrophilum and A. sobria. In biofilm test with microplates, the biofilm absorbance values were determined as 0.048 in the negative control, 0,121 in S. warneri, 0,158 in A. sobria, 0,071 in Y. ruckeri, 0,172 in F. psychrophilum and 0,212 in V. anguillarum. Biofilm formation in the microplate test was determined as V. anguillarum, F. psychrophilum, A. sobria, S. warneri, Y. ruckeri, respectively. The most powerful biofilm formation in microplate method was found in V. anguillarum. The biofilm formation in Congo red agar test was determined as V. anguillarum, A. sobria, S. warneri, F. psychrophilum, Y. ruckeri according to the color change of colony morphology of bacteria produced biofilm. The most powerful biofilm (slime) formation was found in V. anguillarum, A. sobria, S. warneri by producing dry crystalline black colony in Congo red agar. The pink colony-producing F. psychrophilum and Y. ruckeri bacteria did not show biofilm formation in this test. When the biofilm formation in microplate test was evaluated as positive control, it was determined that lysozyme, malic acid, garlic oil, thyme oil were a very effective biofilm inhibition agents when the in vitro antibiofilm effect of these substances were investigated. In the tests conducted with biofilm formation in materials such as wood, metal, fiberglass, glass of all the pathogens have been proven to form biofilm in these materials which are used in many areas in aquaculture facilities. Generally, the biofilm formation power on glass, fiberglass, metal and wood surfaces was determined as S. warneri, A. sobria, V. anguillarum, F. psychrophilum, Y. ruckeri respectively. As a result; S. warneri, A. sobria, V. anguillarum, F. psychrophilum, Y. ruckeri's biofilms formation on the surface of different materials and lysozyme, malic acid, garlic oil, oregano oil substances were found to be the agent of antibiofilm.