Antibacterial Activities of Selected Cameroonian Plants and Their Synergistic Effects with Antibiotics against Bacteria Expressing MDR Phenotypes

Table 5

MIC of different antibiotics after the association of the extract of Picralima nitida fruits at MIC/2, MIC/5 against ten MDR bacteria strains.

Antibiotics	Extract concentration	Bacterial strains, MIC (μg/mL) of antibiotics in the absence and presence of the extract
		AG100	AG100Atet	AG102	CM64	EA3	EA27	EA289	KP55	KP63	PA124
CIP	0; MIC/2; MIC/5	≤0.5; ≤0.5; ≤0.5	128; 16(8)^S; 32(4)^S	32; 16(2)^S; 16(2)^S	≤0.5; ≤0.5; ≤0.5	256; 64(4)^S; 128(2)^S	≤0.5; ≤0.5; ≤0.5	64; 16(4)^S; 32(2)^S	256; 128(2)^S; 256(1)^I	128; 64(2)^S; 64(2)^S	32; 8(4)^S; 8(4)^S
CHL	0; MIC/2; MIC/5	4; 2(2)^S; 4(1)^I	>512; 64(>8)^S; 128(>4)^S	128; 16(8)^S; 32(4)^S	512; 64(8)^S; 128(4)^S	512; 64(8)^S; 128(4)^S	64; 8(8)^S; 32(2)^S	512; 64(8)^S; 128(4)^S	32; 16(2)^S; 16(2)^S	512; 128(4)^S; 256(2)^S	64; 8(8)^S; 32(2)^S
STR	0; MIC/2; MIC/5	4; 2(2)^S; 2(2)^S	>512 256(>2)^S 512(>1)	≤0.5; ≤0.5; ≤0.5	512; 256(2)^S; 512(1)^I	>512; 64(8)^S; 256(>2)^S	16; 16(1)^I; 16(1)^I	16; 16(1)^I; 16(1)^I	16; 16(1)^I; 16(1)^I	128; 128(1)^I; 128(1)^I	>512; 128; 512
AMP	0; MIC/2; MIC/5	32; 16(2)^S; 16(2)^S	>512; 512(1)^I; >512	256; 64(4)^S; 64(4)^S	512; 512(1)^I; 512(1)^I	>512; 128(>4)^S; 512(>1)	64; 64(1)^I; 64(1)^I	>512; >512; >512	>512; >512; >512	>512; >512; >512	>512; 16(>32)^S; 16(>32)^S
TET	0; MIC/2; MIC/5	64; 16(4)^S; 32(2)^S	256; 128(2)^S; 256(1)^I	8; 1(8)^S; 4(2)^S	128; 32(4)^S; 64(2)^S	512; 64(8)^S; 128(4)^S	8; 2(4)^S; 4(2)^S	32; 8(4)^S; 8(4)^S	8; 4(2)^S; 4(2)^S	16; 8(2)^S; 8(2)^S	8; 2(4)^S; 4(2)^S
CLX	0; MIC/2; MIC/5	64; 32(2)^S; 32(2)^S	>512; >512; >512	>512; 128(>4)^S; 256(>2)^S	>512; 256; >512	>512; >512; >512	>512; >512; >512	>512; >512; >512	>512; >512; >512	>512; >512; >512	>512; 512(>1); >512
KAN	0; MIC/2; MIC/5	≤4; ≤4; ≤4	512; 128(4)^S; 128(4)	16; 16(1)^I; 16(1)^I	≤4; ≤4; ≤4	≤4; ≤4; ≤4	>512; 512(>2)^S; >512	32; ≤4(>8)^S; 16(2)^I	32; 8(4)^S; 8(4)^S	512; 128(4)^S; 512(1)^I	128; 64(2)^S; 64(2)^S
ERY	0; MIC/2; MIC/5	64; 32(2)^S; 64(1)^I	512; 256(2)^S; 256(2)^S	16; 16(1)^I; 16(1)^I	256; 32(8)^S; 256(1)^I	32; 8(4)^S; 16(2)^S	8; 4(2)^S; 8(1)^I	128; 128(1)^I; 128(1)^I	64; 16(4)^S; 32(2)^S	128; 64(2)^S; 128(1)^I	128; 8(16)^S; 8(16)^S
NOR	0; MIC/2; MIC/5	32; 16(2)^S; 32(1)^I	512; 128(4)^S; 128(4)^S	128; 32(4)^S; 64(2)^S	16; 8(2)^S; 16(1)^I	16; 4(4)^S; 16(1)^I	32; 16(2)^S; 16(2)^S	64; 32(2)^S; 32(2)^S	64; 32(2)^S; 32(2)^S	64; 4(8)^S; 16(4)^S	128; 32(4)^S; 32(4)^S
FEP	0; MIC/2; MIC/5	512; 256(2)^S; 512(1)^I	512; 128(4)^S; 512(1)^I	512; 512(1)^I; 512(1)^I	>512; 256(>4)^S; >512	256; 64(4)^S; 128(2)^S	512; 252(2)^S; 512(1)^I	512; 512(1)^I; 512(1)^I	>512; >512; >512	512; 256(2)^S; 512(1)^I	512; 512(1)^I; 512(1)^I

(): fold increase in MIC values of the antibiotics after association with plants extract; S: synergy, I: indifference; AMP: ampicillin; FEP: cefepime; CHL: chloramphenicol; KAN: kanamycin; NOR: norfloxacin; STR: streptomycin; TET: tetracycline; CIP: ciprofloxacin; CLX: cloxacillin; ERY: erythromycin.