Figure 2. Role of TCA cycle and iron in the mechanism of Escherichia coli inactivation by (+)-limonene.

Log₁₀ of survival counts of exponential-phase cells of Escherichia coli MG1655 treated with 2,000 μL/L of (+)-limonene (•) following the addition of 500 μM 2,2′-dipyridyl (▪); E. coli MG1655 ΔtonB (□) and E. coli MG1655 ΔacnB (○)treated with 2,000 μL/L of (+)-limonene in LB broth at 37°C. Cells were recovered in LB agar. Data are means ± standard deviations (error bars).