In vitro Growth

Salmonella strains were streaked onto fresh LB agar plates and incubated at 37°C overnight. On the following day, some colonies were re-suspended in LB broth to obtain OD₆₀₀ of 0.4. Next, 1 mL of this suspension was inoculated in 50 mL of fresh, pre-warmed LB broth and incubated with aeration (150 rpm) at 37°C. At hourly intervals from 0 to 12 h, samples were subjected to OD₆₀₀ readings and counting of viable cells on LB agar plates. Counts were reported as the number of colony forming units per mL (CFU/mL). All growth determinations were performed in triplicate.