Figure 3

Detection of live Salmonella cells spiked in spinach by PMA qPCR. Spinach samples were inoculated with 3 × 10¹ CFU/g, 3 × 10² CFU/g and 3 × 10³ CFU/g of live cells, respectively (A); spinach samples were inoculated 3 × 10⁷ dead cells/g and with 3 × 10¹ CFU/g, 3 × 10² CFU/g, and 3 × 10³ CFU/g of live cells, respectively, as indicated (B). Spinach samples were incubated at 35°C up to 24 h. Incubated samples were collected at different time points and treated with PMA or without PMA before DNA extraction. Results were the average of triplicates ± standard deviation.