Fig. 2: Correlation of bacterial growth and generated nitrite in in-vitro model and comparison between susceptible and resistant E. coli strain.

CFU count is correlated with nitrite production of each individual sample. The Spearman correlation of CFU count and nitrite for all strains namely susceptible strain a) (Spearman correlation: 0.82, p-value < 0.001), susceptible strain with drug b) (Spearman correlation: 0.62, p-value: 0.014), the resistant strain c) (Spearman correlation: 0.86, p-value < 0.0001) and the resistant strain with antimicrobial drug d) (Spearman correlation: 0.79, p-value < 0.001) are significant. The solid line in a-d represents the linear least square fit, and the shaded area is the 95% confidence limits. Boxplots show the distribution of CFU counts (f) and generated nitrite (e) across categories from the 25th to the 75th percentile, with a line inside the box indicating the median. The whiskers extend from the box to the smallest and largest values within 1.5 times the interquartile range. Data points outside this range are considered outliers and are shown as individual points (lozenges). Total generated nitrite (e) and CFU count (f) after the addition of antimicrobial drug (time-points 3-5) show a significant difference between the drug-treated and untreated conditions in the susceptible strain. In contrast, no significant difference is observed in the resistant strains, regardless of drug treatment.