Figure 1. Study of the effect of time, pH and rpoS deletion on Escherichia coli BJ4 inactivation by (+)-limonene.

Log₁₀ of survival counts of Escherichia coli BJ4 (wild type: □) and BJ4L1 (ΔrpoS: ) after 10 min, 6 h and 24 h with 200 µL/L of (+)-limonene in citrate-phosphate buffer of pH 4.0 (A) or 7.0 (B) at 20° C. Cells were recovered in TSAYE. Discontinuous line indicates initial cell concentration (3·10⁷ CFU/mL). Arrow indicates survival counts under detection limit. Error bars indicate standard error.