Table 4.
Effect of CFSM on expression (cycle threshold values ± standard error) of virulence genes of enterohaemorragic E. coli O157:H7 after 4 h incubation.
| Gene | PCR efficiencya (%) | LB controlb | Test supernatants from unfermented mediac | CFSM from fermented media by B. bifidumd | CFSM from fermented media by B. crudilactise | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| MRS2 G | MRS2 | MRS2-Wh | MRS2-3′SL | MRS2 G | MRS2 | MRS2-Wh | MRS2-3′SL | MRS2 G | MRS2 | MRS2-Wh | MRS2-3′SL | |||
| recA | 100 | 20 | 21.3 ± 0.6 | 18.2 ± 0.5 | 21.0 ± 0.7 | 20.3 ± 0.3 | 21.2 ± 0.4 | 21.4 ± 1.2 | 23.6 ± 1.9 | 19.9 ± 0.9 | 20.9 ± 0.5 | 23.7 ± 0.2 | 21.7 ± 0.3 | 19.9 ± 1.0 |
| ler | 93 | 18.9 | 25.2 ± 0.4 | 20.3 ± 1.3 | 26.4 ± 1.6 | 19.9 ± 0.8 | 25.6 ± 1.2 | 25.4 ± 0.3 | 28.4 ± 1.6 | 23.8 ± 0.4 | 24.2 ± 1.4 | 25.6 ± 1.0 | 27.8 ± 2.0 | 22.8 ± 2.0 |
| fliC | 97 | 20.8 | 18.2 ± 4.0 | 22.8 ± 1.4 | 24.1 ± 1.1 | 23.4 ± 2.0 | 19.1 ± 0.3 | 24.9 ± 4.2 | 26.0 ± 4.9 | 18.7 ± 1.5 | 19.8 ± 1.6 | 21.7 ± 3.7 | 25.3 ± 3.1 | 19.3 ± 0.6 |
| luxS | 91 | 23.6 | 26.8 ± 0.9 | 20.7 ± 1.6 | 30.1 ± 1.9 | 25.0 ± 1.3 | 27.7 ± 1.0 | 28.3 ± 0.9 | 32.6 ± 4.7 | 25.4 ± 1.5 | 27.4 ± 0.3 | 26.8 ± 3.1 | 29.8 ± 3.3 | 25.8 ± 2.2 |
| stxB2 | 95 | 26.1 | 28.8 ± 1.0 | 25.7 ± 1.0 | 33.4 ± 2.4 | 26.5 ± 2.6 | 29.3 ± 3.0 | 30.4 ± 1.5 | 35.3 ± 1.0 | 27.6 ± 0.5 | 29.7 ± 2.5 | 30.1 ± 2.3 | 33.8 ± 3.8 | 27.8 ± 2.0 |
| qseA | 91 | 22.5 | 24.1 ± 0.4 | 26.3 ± 0.4 | 24.4 ± 0.8 | 21.9 ± 0.5 | 24.7 ± 1.4 | 25.3 ± 2.0 | 27.0 ± 2.1 | 22.7 ± 1.2 | 24.1 ± 0.9 | 23.5 ± 3.0 | 25.2 ± 1.0 | 23.3 ± 1.0 |
a
PCR efficiency: E = [(10(-1/slope))/2] x 100%.
b
E. coli O157:H7 grown in LB broth for 4 h.
c
E. coli O157:H7 grown in LB broth supplemented with unfermented culture media CFSM for 4 h.
d
E. coli O157:H7 grown in LB broth supplemented with fermented concentrated culture media CFSM from B. bifidum for 4 h.
e
E. coli O157:H7 grown in LB broth supplemented with fermented concentrated culture media CFSM from B. crudilactis for 4 h.