Table 4.
Zones of inhibition (mm) produced by antimicrobial biocides against Gram-negative MDR isolates in the absence and presence of interfering substance BSA at 3 and 10 g/L (+10 g/L YE) (+/− Standard deviation).
| Gram Negative Isolate | BSA (g/L) | Biocide Test Substance | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| BAC | Peracetic Acid | Triameen | ||||||||
| 0.01% | 0.1% | 1% | 0.01% | 0.1% | 1% | 0.01% | 0.1% | 1% | ||
| E. coli | 0 3 10 * |
7.5 (+/−0.1) A 7.4 (+/−0.6) A 7.5 (+/−0.8) A |
9.0 (+/−0.7) C 8.5 (+/−0.7) B 9.5 (+/−1.0) C |
14.8 (+/−1.0) H 15.0 (+/−1.4) H 14.5 (+/−1.6) H |
8.0 (+/−0.1) B 7.8 (+/−0.7) B 7.5 (+/−0.6) A |
18.0 (+/−0.9) K 20.4 (+/−1.4) E 20.3 (+/−1.1) E |
39.0 (+/−0.7) M 40.5 (+/−0.8) M 39.0 (+/−1.1) M |
8.3 (+/−0.4) B 8.0 (+/−0.6) B 7.5 (+/−0.8) A |
14.0 (+/−1.2) J 16.5 (+/−0.8) J 16.5 (+/−0.6) J |
20.5 (+/−1.4) E 20.4 (+/−0.6) E 20.6 (+/−1.0) E |
| K. pneumoniae | 0 3 10 * |
0 (+/−0) 0 (+/−0) 0 (+/−0) |
7.0 (+/−0.3) A 7.0 (+/−1.0) A 0 (+/−0) |
9.8 (+/−0.4) D 9.0 (+/−1.2) C 9.5 (+/−1.2) C |
8.0 (+/−0.5) B 8.0 (+/−0.6) B 7.0 (+/−0.6) A |
20.3 (+/−1.0) E 20.4 (+/−0.6) E 20.1 (+/−1.1) E |
40.0 (+/−0.9) M 34.5 (+/−1.0) N 34.5 (+/−1.2) N |
9.0 (+/−0.3) C 9.5 (+/−0.2) C 9.0 (+/−0.7) C |
16.0 (+/−1.1) J 16.0 (+/−0.8) J 15.8 (+/−1.0) J |
20.3 (+/−0.8) E 20.3 (+/−0.4) E 20.5 (+/−1.0) E |
| A. baumannii | 0 3 10 * |
8.5 (+/−0.1) B 7.0 (+/−1.0) A 7.0 (+/−1.0) A |
14.0 (+/−1.0) 11.0 (+/−0.8) 10.0 (+/0.6) D |
20.5 (+/−0.8) E 18.5 (+/−1.0) I 18.9 (+/−1.0) I |
9.0 (+/−1.4) C 9.0 (+/−1.1) C 9.5 (+/−0.6) C |
20.4 (+/−0.4) 20.3 (+/−1.0) E 20.0 (+/−0.8) E |
41.0 (+/−1.0) M 40.5 (+/−0.8) M 40.5 (+/−1.2) M |
8.5 (+/−1.2) B 8.3 (+/−1.0) B 8.8 (+/−0.4) C |
19.0 (+/−0.9) I 18.9 (+/−0.4) I 19.0 (+/−0.8) I |
24.5 (+/−0.8) Q 24.5 (+/−0.6) Q 25.0 (+/−0.2) Q |
| P. aeruginosa | 0 3 10 * |
0 (+/−0) 0 (+/−0) 0 (+/−0) |
10 (+/−0.8) D 7.8 (+/−1.1) B 7.0 (+/−0.7) A |
14.5 (+/−1.1) H 10.5 (+/−1.1) D 9.0 (+/−0.8) C |
7.5 (+/−0.4) A 7.5 (+/−0.2) A 7.5 (+/−0.3) A |
16.5 (+/−1.3) J 16.5 (+/−1.1) J 14.8 (+/−0.4) H |
44.3 (+/−1.7) O 38.5 (+/−0.8) M 34.5 (+/−1.5) N |
9.5 (+/−0.7) C 8.0 (+/−1.0) B 7.3 (+/−0.4) A |
14.5 (+/−0.7) H 14.3 (+/−0.9) H 14.0 (+/−1.8) H |
28.0 (+/−0.8) R 19.5 (+/−1.4) E 22.3 (+/−0.8) P |
| P. fulva | 0 3 10 * |
0 (+/−0) 0 (+/−0) 7.0(+/−0.4) A |
10 (+/−0.5) D 9.0 (+/−0.4) C 10 (+/−1.1) D |
16.0(+/−0.8) J 16.5(+/−1.1) J 18.0(+/−0.5) I |
8.8 (+/−0.3) C 9.5 (+/−0.7) C 9.0 (+/−0.6) C |
17.7 (+/−0.4) K 16.8 (+/−1.4) J 17.8 (+/−0.4) K |
38.6 (+/−1.4) M 38.4 (+/−1.3) M 34.2 (+/−2.1) N |
9.3 (+/−0.4) C 9.5 (+/−0.8) C 10 (+/−0.6) D |
16.0 (+/−0.3) J 16.3 (+/−0.5) J 15.8 (+/−1.3) J |
22.6 (+/−1.4) P 22.5 (+/−1.1) P 22.5 (+/−0.7) P |
| P. fluorescens | 0 3 10 * |
7.8 (+/−0.4) B 8.0 (+/−0.1) B 7.0 (+/−0.1) A |
11.0 (+/−1.4) F 12.0 (+/−0.1) G 10.0 (+/−0.1) D |
19.3 (+/−1.3) I 20.0 (+/−2.1) E 18.5 (+/−1.5) I |
10.5 (+/1.8) D 9.0 (+/−1.0) C 9.5 (+/−0.8) C |
18.1 (+/−0.7) I 18.0 (+/−1.2) I 16.0 (+/−0.8) J |
38.6 (+/−2.1) M 34.3 (+/−1.1) N 34.0 (+/−1.8) N |
11.3 (+/−1.4) F 10 (+/−0.4) D 10.8 (+/−1.6) F |
22.8 (+/−1.1) P 22.5 (+/−0.5) P 22.5 (+/−0.8) P |
30.0 (+/−0.6) T 25.0 (+/−0.9) Q 22.5 (+/−1.2) P |
| P. mirabilis | 0 3 10 * |
0 (+/−0) 0(+/−0) 0(+/−0) |
8.5 (+/−0.7) B 8.0 (+/−0.3) B 8.0 (+/−0.9) B |
14.5 (+/−1.5) H 14.8 (+/−1.4) H 14.6 (+/−0.8) H |
7.5(+/−0.4) A 8.0(+/−1.0) B 8.5(+/−0.2) B |
26.0 (+/−0.9) L 20.0 (+/−1.6) E 20.3 (+/−0.4) E |
45.0 (+/−1.7) O 40.5 (+/−1.1) M 40.3 (+/−1.4) M |
9.5 (+/−0.4) C 9.0 (+/−0.6) C 10 (+/−1.3) D |
26.0 (+/−1.4) L 26.0 (+/−0.2) L 26.0 (+/−0.5) L |
33.0 (+/−2.0) S 28.5 (+/−1.8) R 28.5 (+/−0.6) R |
* 0 g/L BSA plus 10 g/L yeast extract. Alphabetical lettering indicates there is a significant difference in zone diameter between strains at p < 0.05, where groups displaying the same letter are statistically similar whilst those denoted by a different letter are statistically different.