Antibacterial and Antibiotic-Modifying Activity of Methanol Extracts from Six Cameroonian Food Plants against Multidrug-Resistant Enteric Bacteria
Table 7
MIC of different antibiotics after the association of the extract of leaves from Psidium guajava at MIC/2, MIC/4 against ten MDR bacteria strains.
Antibiotic
Bacterial strains and MIC (μg/mL) of antibiotics in the absence and presence of the extrac
Concentration of the extract
PA124
AG102
AG100Atet
EA289
CM64
KP55
KP63
NEA16
PS2636
BM47
PBS (%)
CHL
0
128
8
128
256
256
32
32
16
64
128
MIC/2
32 (0.25)
4 (0.5)
64 (0.5)
256 (1)
256 (1)
32 (1)
16 (0.5)
8 (0.5)
32 (0.25)
32 (0.25)
70
MIC/4
32 (0.25)
8 (1)
128 (1)
256 (1)
256 (1)
32 (1)
32 (1)
16 (1)
64 (1)
128 (1)
10
CIP
0
64
4
>64
>64
>64
2
<0.5
4
8
<0.5
MIC/2
32 (0.5)
4 (1)
>64 (≥1)
16 (<0.25)
64 (<1)
2 (1)
<0.5 (≥1)
2 (0.5)
1 (0.125)
<0.5 (≥1)
50
MIC/4
32 (0.5)
4 (1)
>64 (≥1)
>64 (≥1)
64 (<1)
2 (1)
<0.5 (≥1)
4 (1)
4 (0.5)
<0.5 (≥1)
30
TET
0
16
16
32
64
4
32
2
4
2
32
MIC/2
32 (2)
4 (0.25)
32 (1)
32 (0.5)
4 (1)
16 (0.5)
<0.5 (<0.25)
<0.5 (<0.125)
<0.5 (<0.25)
16 (0.5)
70
MIC/4
32 (2)
16 (1)
32 (1)
32 (0.5)
4 (1)
32 (1)
1 (0.5)
4 (1)
<0.5 (<0.25)
32 (1)
30
ERY
0
128
8
128
256
8
16
4
16
16
16
MIC/2
128 (1)
4 (0.5)
128 (1)
128 (0.5)
<2 (<0.25)
16 (1)
2 (0.5)
16 (1)
16 (1)
16 (0.5)
50
MIC/4
128 (1)
4 (0.5)
128 (1)
128 (0.5)
<2 (<0.25)
16 (1)
4 (1)
16 (1)
16 (1)
16 (1)
10
KAN
0
128
4
8
32
32
32
<2
16
16
8
MIC/2
128 (1)
<2 (<0.5)
8 (1)
4 (0.5)
32 (1)
8 (0.25)
<2 (≥1)
8 (0.5)
4 (0.25)
8 (1)
50
MIC/4
128 (1)
<2 (<0.5)
8 (1)
32 (1)
32 (1)
32 (1)
<2 (≥1)
8 (0.5)
16 (1)
8 (1)
20
STP
0
256
>256
>256
128
8
64
8
16
>256
64
MIC/2
128 (0.5)
16 (<0.062)
128 (<0.5)
128 (1)
4 (0.5)
64 (1)
4 (0.5)
16 (1)
128 (<0.5)
16 (0.25)
70
MIC/4
128 (0.5)
128 (<0.5)
256 (<1)
128 (1)
8 (1)
64 (1)
8 (1)
16 (1)
>256 (≥1)
16 (0.25)
40
AMP
0
>256
>256
>256
>256
>256
>256
>256
>256
>256
>256
MIC/2
256 (<1)
>256 (≥1)
>256 (≥1)
256 (<1)
128 (<0.5)
>256 (≥1)
128 (<0.5)
>256 (≥1)
256 (<1)
>256 (≥1)
50
MIC/4
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
10
CEF
0
>256
>256
>256
>256
>256
>256
>256
>256
>256
>256
MIC/2
256 (<1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
10
MIC/4
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
>256 (≥1)
00
[TET: tetracycline, CIP: ciprofloxacin, STP: streptomycin, KAN: kanamycin, CHL: chloramphenicol, ERY: erythromycin, AMP: ampicillin, and CEF: cefepime]. strains: Escherichia coli [AG102, AG100Atet], Pseudomonas aeruginosa [PA124], Enterobacter aerogenes [CM64, EA27, EA289], Klebsiella pneumonia [KP55, KP63], Providencia stuartii [NAE16], and Enterobacter cloacae [BM47]. : percentage of bacteria strain on which synergism has been observed. Values in parenthesis are fractional inhibitory concentration (FIC) of the antibiotics after association with plants extract; S: synergy; I: indifference. The values in bold represent the cases of synergy between extract and antibiotic.
