Antibacterial and Antibiotic Modifying Potential of Crude Extracts, Fractions, and Compounds from Acacia polyacantha Willd. against MDR Gram-Negative Bacteria
Table 6
Antibiotic resistance modulatory activity of 3-O-[β-galactopyranosyl-(1→4)-β-galactopyranosyl]-oleanolic acid (8) against MDR Gram-negative bacteria.
Antibiotics
Extract concentration
Bacteria, MIC (μg/mL) and modulating factors of compound 8 (in bracket)
ATCC8739
AG102
ATCC13048
CM64
KP55
KP63
PA124
NEA16
PBS (%)
ERY
0
128
256
256
256
256
256
256
256
MIC/2
256 (0.5)
128 (2)
256 (1)
128 (2)
128 (2)
64 (4)
64 (4)
128 (2)
75
MIC/4
128 (1)
128 (2)
128 (2)
256 (1)
256 (1)
64 (4)
128 (2)
256 (1)
50
CLX
0
256
1024
> 1024
> 1024
1024
512
> 1024
> 1024
MIC/2
1024 (0.25)
> 1024 (> 1)
> 1024 (≥ 1)
> 1024 (≥ 1)
1024 (1)
1024 (0.5)
> 1024 (≥ 1)
> 1024 (≥ 1)
0
MIC/4
> 1024(>0.25)
> 1024 (> 1)
> 1024 (≥ 1)
> 1024 ≥ 1)
1024 (1)
> 1024 (> 0.5)
> 1024 (≥ 1)
> 1024 (≥ 1)
0
KAN
0
16
16
< 2
16
4
64
8
64
MIC/2
4 (4)
64 (0.25)
128 (0.015)
128 (0.125)
< 2 (2)
256 (0.25)
8 (1)
128 (0.5)
25
MIC/4
128 (0.125)
32 (0.25)
128 (0.015)
128 (0.125)
< 2 (2)
256 (0.25)
8 (1)
128 (0.5)
12.5
GEN
0
32
16
16
16
256
32
128
256
MIC/2
256 (0.125)
64 (0.25)
128 (0.125)
8 (2)
64 (4)
256 (0.125)
64 (2)
256 (1)
37.5
MIC/4
256 (0.125)
> 256 (> 0.062)
128 (0.125)
128 (0.125)
128(2)
> 256 (>0.125)
128 (1)
128 (2)
25
DOX
0
< 1
4
16
16
4
8
64
32
MIC/2
< 1 (≤ 1)
2 (2)
16 (1)
32 (0.5)a
< 1 (> 4)
2 (4)
32 (2)
16 (2)
62.5
MIC/4
< 1 (≤ 1)
4 (1)
32 (0.5)a
32 (0.5)a
< 1 (> 4)
2 (4)
32 (2)
32 (1)
37.5
CHL
0
2
32
16
256
64
32
256
64
MIC/2
2 (1)
16 (2)
16 (1)
256 (1)
32 (2)
32 (1)
256 (1)
64 (1)
25
MIC/4
1 (2)
32(1)
16 (1)
256 (1)
32 (2)
16 (2)
256 (1)
64 (1)
37.5
NOR
0
4
8
32
32
8
8
64
32
MIC/2
2 (2)
8 (1)
> 128 (> 0.25)
64 (0.5)
4 (2)
8 (1)
32 (2)
128 (0.125)
37.5
MIC/4
< 1 (> 4)
2 (4)
128 (0.25)
64 (0.5)
4 (2)
4 (2)
32 (2)
128 (0.125)
62.5
CIP
0
< 0.5
1
8
8
< 0.5
1
64
8
MIC/2
< 0.5 (≤ 1)
< 0.5 (> 2)
64 (0.125)
64 (0.125)
< 0.5 (≤ 1)
4 (0.25)
64 (1)
64 (0.125)
12.5
MIC/4
2 (0.25)
< 0.5 (> 2)
64 (0.125)
64 (0.125)
1 (2)
2 (0.5)
64 (1)
64 (0.125)
12.5
ERY: erythromycin; CLX: cloxacillin; KAN: kanamycin; GEN: gentamycin; DOX: doxyciclin; CHL: chloramphenicol; NOR: norfloxacin; CIP: ciprofloxacin; bacterial strains: Escherichia coli (AG102, ATCC8739); Enterobacter aerogenes (ATCC13048, CM64); Klebsiella pneumonia (KP55, KP63); P. aeruginosa PA124; Providencia stuartii NEA16; PBS: percentage of bacteria strain on which synergism has been observed. (): ameliorating factor of the antibiotics after association with compound 8; S: synergy; I: indifference; a: antagonist; values in bold: case of synergy [19, 20].
