Figure 5

Inhibitory effect of the SP1 supernatant over a range of Gram-positive and Gram-negative bacteria. Biofilms of various Gram-positive and Gram-negative bacteria were developed in the presence or absence of the SP1 supernatant (5% V/v) in 96-well microtiter plate. The plate was incubated at 30°C for 36 h, followed by crystal violet staining and spectrophotometric absorbance measurements (OD₅₇₀). The ratio of biofilm absorbance/planktonic absorbance was calculated, and this value used to calculate the "biofilm formation" on the y axis. The various Gram-positive and Gram-negative bacteria used in the wells are listed on X axis. Bars indicate means ± standard errors for six replicates.