Figure 4. NaOH-SDS treatment did not lyse gram-positive bacteria in 5 min.

(A) The mid-log phase culture of 2 gram-positive bacterial strains (Staphylococcus aureus and Enterococcus faecalis) and Escherichia coli (gram-negative bacteria used as control) were treated with the NaOH-SDS solution for the indicated time. The numbers of bacteria that were measured by the UF-1000i were converted into percentages that were relative to the control that was treated with an equal volume of PBS. Each symbol represents the average of 3 independent experiments, and the error bars represent the standard error of the mean. (B) Representative BACT scattergrams of NaOH-SDS-treated bacterial culture incubated for 5 or 60 min or the control.