TABLE 6.
Influence of fluid dynamics biofilm growth and characteristic.
| Microorganism | Flow conditions tested | Influence on biofilm growth and characteristic | References |
| Bacillus cereus | Shear stress | Biofilm density increased with an increase in shear stress, while the biofilm thickness decreased | Lemos et al., 2015 |
| P. aeruginosa | Shear stress | Shear acts as a cue for surface adhesion and activates c-di-GMP signaling, increasing the strength of bacterial adhesion | Rodesney et al., 2017 |
| E. coli | Shear stress | Low shear stress resulted in uniform biofilm growth while high stress resulted in biofilm growth from the edge toward the center of the channel | Thomen et al., 2017 |
| S. aureus | Shear stress | Increased shear stress increases EPS production, resulting in higher biofilm density | Hou et al., 2018 |
| Thalassospira strain | Shear stress | Flow velocity of 1.66 mm/s is the optimal rate for fast and strong biofilm adhesion, while too high shear stress prevented biofilm formation and removed adhered biofilms | Liu et al., 2019 |
| Actinobacillus succinogenes | Shear stress | Enhanced bacterial metabolic activities and biofilm viability under high shear condition | Mokwatlo et al., 2020 |
| E. coli and S. aureus | Shear stress | Higher shear force was required to reduce bacterial adhesion on the hydrophilic surface compared with the hydrophobic surface | Zhu et al., 2020 |
| E. coli | Laminar and turbulent flow | Turbulent flow significantly reduced bacterial adhesion compared with laminar flow | Fink et al., 2015 |
| P. fluorescens | Linear flow | High flow velocities resulted in thinner biofilms with higher cell densities and contents of the matrix/extracellular polysaccharides | Araújo Paula et al., 2016 |
| E. coli | Laminar and turbulent flow | Laminar flow promotes biofilm growth over a 72 h period, while turbulent flow after 48 h causes reduction in biofilm biomass | Oder et al., 2018 |
| S. aureus and E. coli | Static and dynamic | Greater reduction in bacterial adhesion to hydrophobic surfaces under flow conditions | Hizal et al., 2017 |
| F. nucleatum and P. gingivalis | Static and dynamic | Loosely formed biofilm and reduced bacterial count were observed under the dynamic condition | Song W.S. et al., 2017 |
| Biofilm from human saliva | Static and dynamic | Biofilm viability in the static model was lower compared with the semi-dynamic model | Santos et al., 2019 |