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Table 1 Zones of growth inhibition for E. coli and L. acidophilus

From: 600-ns pulsed electric fields affect inactivation and antibiotic susceptibilities of Escherichia coli and Lactobacillus acidophilus

Pulse #E. coliL. acidophilus
13.5 kv cm−1
Sham16 (I)0.216 (I)0.211 (R)0.611 (R)0.613 (R)0.613 (R)0.614 (I)0.614 (I)0.6
116 (I)016 (I)011 (R)011 (R)0.613 (R)014 (R)014 (I)114 (I)0
516 (I)016 (I)011 (R)011 (R)0.613 (R)114 (R)0.615 (I)114 (I)0.6
1016 (I)016 (I)011 (R)0.611 (R)0.513 (R)114 (R)0.615 (I)114 (I)1
10016 (I)016 (I)012 (R)012 (R)0.614 (R)114 (R)016 (S)0.714 (I)0
100018 (S)0.316 (I)012 (R)011 (R)0.616 (I)114 (R)0.319 (S)114 (I)0.6
18.5 kv cm−1
Sham16 (I)0.216 (I)0.211 (R)0.611 (R)0.613 (R)0.613 (R)0.614 (I)0.614 (I)0.6
117 (I)116 (I)0.311 (R)0.612 (R)0.313 (R)0.614 (R)014 (I)014 (I)0.6
518 (S)016 (I)0.612 (R)012 (R)0.613 (R)0.614 (R)014 (I)114 (I)0.3
1019 (S)0.616 (I)012 (R)012 (R)013 (R)014 (R)114 (I)114 (I)0
10020 (S)016 (I)0.612 (R)0.612 (R)0.614 (R)114 (R)0.816 (S)014 (I)1
100022 (S)016 (I)014 (I)0.611 (R)015 (I)014 (R)019 (S)1.414 (I)0
23.5 kv cm−1
Sham16 (I)0.216 (I)0.211 (R)0.611 (R)0.613 (R)0.613 (R)0.614 (I)0.614 (I)0.6
117 (I)0.616 (I)011 (R)011 (R)0.614 (R)014 (R)0.314 (I)214 (I)0
517 (I)016 (I)0.611 (R)1.211 (R)0.615 (I)0.614 (R)0.615 (I)0.814 (I)0.3
1019 (S)116 (I)012 (R)111 (R)0.615 (I)0.614 (R)0.316 (S)0.614 (I)0.3
10022 (S)0.516 (I)016 (S)012 (R)0.515 (I)114 (R)0.618 (S)114 (I)0
  1. Following a 13.5, 18.5 or 23.5 kV cm−1 600-ns PEF and its respective TE, E. coli and L. acidophilus were exposed to the following antibiotic-soaked discs: kanamycin (30 µg) and tobramycin (10 µg) and vancomycin (30 µg) and ampicillin/sulbactam (10/10 µg), respectively. Measured zones of growth inhibition (diameter, mm) are reported. Values represent the mean of 3 replicates, the standard deviation (SD) of each value is provided. Susceptibility is expressed as R (resistant), I (intermediate) or S (susceptible). No observable growth is indicated by an asterisk (*)