Table 2.
Size of subpopulations (average ± standard deviation) of enterotoxigenic Escherichia coli strains (ECL 20440, ECL 23141 and ECL 21858) stained with PI, BOX, cFDA, CTC and EB after exposure to two different concentrations of phenolic‐rich extract from acerola by‐products (PEA, 31·25 and 62·50 mg ml−1)
| Cellular structure or function disruption | Enterotoxigenic E. coli strains | Treatments | ||
|---|---|---|---|---|
| Control (without exposure to extract) | PEA (31·25 mg ml−1) | PEA (62·50 mg ml−1) | ||
| Size of subpopulations (%) | ||||
| Permeabilized cells (PI+) | ECL 20440 | 5·6 ± 0.2Ac | 11·5 ± 2.7Bb | 28·7 ± 0.1Aa |
| ECL 23141 | 3·5 ± 0.5Bc | 17·5 ± 2.0Ab | 29·5 ± 1.8Aa | |
| ECL 21858 | 3·0 ± 1.8Bc | 10·0 ± 0.3Bb | 24·6 ± 1.9Ba | |
| Depolarized cells (BOX+) | ECL 20440 | 10·2 ± 0.4Ac | 24·5 ± 2.7Bb | 49·0 ± 3.5Ba |
| ECL 23141 | 8·1 ± 1.0Bc | 18·8 ± 1.5Cab | 25·2 ± 0.8Ca | |
| ECL 21858 | 7·6 ± 1.1Bc | 68·1 ± 2.3Ab | 86·9 ± 1.9Aa | |
| Cells without enzymatic activity (cF−) | ECL 20440 | 9·1 ± 0.6Ab | 90·5 ± 2.6Aa | 93·0 ± 1.4Aa |
| ECL 23141 | 5·0 ± 1.6Bb | 91·3 ± 4.7Aa | 96·4 ± 1.4Aa | |
| ECL 21858 | 8·9 ± 1.6Ac | 87·4 ± 1.7Ab | 95·1 ± 2.0Aa | |
| Cells without respiratory activity (CTC−) | ECL 20440 | 5·4 ± 1.1Ab | 58·0 ± 3.2Ca | 61·6 ± 2.3Ca |
| ECL 23141 | 6·0 ± 0.2Ac | 90·7 ± 1.5Ba | 73·8 ± 1.3Bb | |
| ECL 21858 | 7·7 ± 1.7Ab | 97·7 ± 3.7Aa | 99·3 ± 1.4Aa | |
| Cells with compromised efflux pump activity (EB+) | ECL 20440 | 10·5 ± 3.4Ac | 31·2 ± 4.3Bb | 45·6 ± 1.9Ba |
| ECL 23141 | 11·9 ± 0.8Ac | 27·5 ± 3.1Cb | 47·4 ± 1.0Ba | |
| ECL 21858 | 8·6 ± 0.7Bc | 47·6 ± 1.9Ab | 72·2 ± 2.5Aa | |
Different superscript lowercase letters (a–c) in the same row denote significant differences (P < 0·05), based on Kruskal–Wallis test. Different superscript capital letters (A–C) in the same column denote significant differences (P < 0·05) among different strains, for a same treatment and fluorescence stain, based on Kruskal–Wallis test.