Antibacterial and antibiotic resistance modulatory activities of leaves and bark extracts of Recinodindron heudelotii (Euphorbiaceae) against multidrug-resistant Gram-negative bacteria

Table 3 Antibiotic resistance modulatory activity of leaves extract of R. heudelotii

Antibiotics^a	Extracts concentration^b	Bacteria, MIC (μg/mL) and modulating factors (in bracket)									Modulating effect (%)^b
		E. coli			E. aerogenes			K. pneumoniae	P. stuartuii	P. aeruginosa
		AG100	AG102	AG100_Tet	CM64	EA289	EA298	K24	NEA16	PA124
AMP	0	-	-	-	-	-	-	-	-	-
	MIC/2	-	-	-	-	-	-	-	-	-	0
	MIC/4	-	-	-	-	-	-	-	-	-	0
CHL	0	8	32	64	256	128	64	64	64	64
	MIC/2	8 (1)	16 (2)	32 (2)	256 (1)	128 (1)	32 (2)	32 (2)	32 (2)	32 (2)	66.67
	MIC/4	8 (1)	16 (2)	64 (1)	256 (1)	256 (0.5)	64 (1)	64 (1)	32 (2)	32 (2)	33.33
CIP	0	≤0.5	≤0.5	128	64	128	1	128	1	32
	MIC/2	≤0.5 (na)	≤0.5 (na)	64(2)	32 (2)	128 (1)	1 (1)	64 (2)	1 (1)	32 (1)	33.33
	MIC/4	≤0.5 (na)	≤0.5 (na)	128(1)	64 (1)	128 (1)	1 (1)	64 (2)	1 (1)	32 (1)	11.11
KAN	0	64	4	8	2	16	32	4	16	128
	MIC/2	4 (16)	1 (4)	2 (4)	1 (2)	4 (4)	32 (1)	2 (2)	8 (2)	64 (2)	88.89
	MIC/4	16 (4)	4 (1)	2 (4)	2 (1)	8 (2)	32 (1)	2 (2)	8 (2)	64 (2)	66.67
ERY	0	32	64	-	-	64	16	128	16	128
	MIC/2	32 (1)	64 (1)	-	-	64 (1)	16 (1)	128 (1)	8 (2)	64 (2)	22.22
	MIC/4	32 (1)	64 (1)	-	-	64 (1)	16 (1)	128 (1)	8 (2)	128 (1)	11.11
TET	0	2	8	32	16	32	4	16	4	16
	MIC/2	≤0.5 (≥4)	4 (2)	4 (8)	4 (4)	4 (8)	2 (2)	8 (2)	2 (2)	16 (1)	88.89
	MIC/4	≤0.5 (≥4)	4 (2)	8 (4)	16 (1)	8 (4)	2 (2)	8 (2)	2 (2)	16 (1)	77.78

^a: TET tetracycline, KAN kanamycin, ERY erythromycin, CHL chloramphenicol, CIP ciprofloxacin, AMP ampicillin;; −: MIC not detected at up to 256 μg/mL; (): Modulating factor; na: not applicable,
^b: MIC Minimal Inhibitory Concentration. ^c: Percentage of antibiotic’s modulating effect by the plant extracts. Values in bold represent modulating factor ≥ 2 and modulating effect observed on more than 70% of the tested MDR bacteria

ISSN: 2662-7671