| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1176-2 | ||||
Resumo:Bacteriophages are important tools in bacterial control, and their study is relevant for application in materials used for prostheses. Thus, the objective of this study was to evaluate the reduction of biofilms mediated by bacteriophages aiming at control in elements of dental and orthopedic prostheses composed by emergency. The samples of elements of dental and orthopedic prostheses were provided by the Center for Teaching and Research in Dental Implants (CEPID) of the Federal University of Santa Catarina (UFSC) and the bacteriophages belonging to the bank of isolates of the Laboratory of Applied Virology, derived from bacterial culture clinic at the University Hospital/UFSC. Such phages, comprising 5 types, were tested for their ability to grow with a lytic profile in Pseudomonas aeruginosa following the agar double-layer methodology (SEJAS, et al., 2003). In vitro biofilm induction was performed using a 24-hospitalization plate through the experience of mourning discs in a medium containing the bacterial suspension at a known titer (10 -8) and incubation (37 °C) for 7 days, as adapted the Freitas study; Sand and Simonetti (2010). Every 24 hours, the nutrient medium was changed. After this period, the disks were washed, fixed, dehydrated, stained, metalized, and analyzed in Scanning Electron Microscopy (SEM), both processes were performed in triplicate. Biofilm formation was also evaluated in polystyrene microtiter plates by the Crystal Violet method described by Stepanovic et al., (2007) with minor modifications, following the steps of incubation, fixation, colors, and absorbance reading in the microtiter plate, respectively. The evaluation of biofilm formation was performed by reading the absorbance of each well using a plate reader, at a wavelength of 600 nm. The evaluation and incorporation of bacteriophages in the control of biofilms in specimens of encouragement were carried out by applying 1000 μL of the solution of each of the isolated bacteriophages (MOIs 0.01; 0.1 and 1), being treated two experiments prepared and Destructive agents: Experiment 1 – disaggregation activity and destruction of established bacterial biofilms. Experiment 2 – Prophylactic activity of bacteriophages in combating biofilm formation. In experiment 1, biofilms were generated under the membrane specimens with the methodology described above, and the phages were used for biofilm disaggregation purposes; in experiment 2, the phages were made available in sterile test specimens, and after 1 h the bacterial biofilm pressure was applied. The specimens containing bacteria and bacteriophages were incubated at 37 ºC for 24/48 hours and the prophylactic activity and biofilm control were verified by Scanning Electron Microscopy and colony count CFU/mL. However, the preliminary results obtained, particularly that the use of bacteriophages isolated so far, were efficient in disaggregating and destroying the previously tested biofilm, as well as acting effectively in the prophylactic activity of biofilm formation, given that after its application there was no there was bacterial growth on the surface of the yeast disks, observed in SEM and in the reduction in the number of colonies when compared to the control. However, bacteriophages were able to inhibit bacterial growth and induce planktonic bacterial breakdown, being possible therapeutic targets for the development of biotechnological tools to control microbial resistance. Palavras-chave: biofilm, Pseudomonas aeruginosa, titanium, bacteriophages Agência de fomento:UNIVERSIDADE FEDERAL DE SANTA CATARINA | |||||