부산대학교 도서관

Introduction: Biofilm formation has different stage and classification based on bacteria strain, culture vessel and technical aspect used. Biofilm is formed in culture vessel to represent an original mode of infection towards human. Microbial concentration, growth medium, supplement and incubation time are among multiple factors to successfully form biofilm in culture vessel. Objectives: This study aimed to identify the optimum condition of biofilm to be formed in 96-well plate by culturing P. aeruginosa and S. pyogenes. Materials and Methods: We utilized the infectious and pathogenic bacteria, P. aeruginosa and S. pyogenes strains. These bacteria were cultured in Mueller-Hinton Broth (MHB) and Tryptic Soy Broth (TSB) at two different optical densities (OD 0.05 and 0.1). After certain incubation time, the formed biofilm was stained by using 0.1% crystal violet. The stained bacteria were aggregated and measured by using a micro plate reader. Biofilm was then classified based on the bacterial adherence to the plate. Results: Results showed that P. aeruginosa and S. pyogenes biofilms were strongly formed on days three and five in MHB and TSB. However, the strongest biofilm formation was seen on day three after P. aeruginosa being incubated in MHB at OD 0.1 and after S. pyogenes being incubated in MHB at OD 0.05. Biofilm formation is ranged between weak, moderate and strong in accordance to the density of bacterial adhesion. Conclusion: P. aeruginosa and S. pyogenes biofilms were optimized at specific optical density (0.1 and 0.05, respectively) for three days' cultivation in MHB. [ABSTRACT FROM AUTHOR]