Combined antibacterial effect of essential oils from three most commonly used Ethiopian traditional medicinal plants on multidrug resistant bacteria

Table 3 Inhibition zone (mm) of combined essential oils against MDR bacteria at AAU, 2018

TMP	μl/disc	Gram positive		Gram negative
		S.aureus		E.coli		K. pneumoniae
		ATCC	MRSA	ATCC	MDR	ATCC	MDR
T. schimper + B.cuspidata (1:1 ratio)	5	19 ± 1.0	18 ± 1.2	20 ± 1.0	21 ± 0.1	27 ± 1.0	27 ± 0.8^#
	10	29 ± 1.2	29 ± 0.5^**	23 ± 1.2	25 ± 0.1^¥	29 ± 1.2	28 ± 0.3^#
	15	33 ± 0.1	33 ± 0.6^**	28 ± 0.1	26 ± 0.5^¥	33 ± 0.7	34 ± 0.1^##
	20	38 ± 0.3	39 ± 0.8^***	29 ± 0.1	29 ± 0.8^¥¥	35 ± 1.4	35 ± 0.5^##
B. cuspidata + B. ogadensis (1:1 ratio)	5	20 ± 0.4	20 ± 0.1	16 ± 0.4	15 ± 0.9	19 ± 0.7	15 ± 0.4
	10	25 ± 0.5	26 ± 0.3^*	18 ± 0.6	23 ± 0.2	24 ± 0.4	23 ± 0.2
	15	28 ± 0.3	27 ± 0.3^**	24 ± 0.5	26 ± 0.4^¥	27 ± 1.2	26 ± 0.4^#
	20	32 ± 0.1	32 ± 0.1^***	26 ± 0.8	27 ± 0.1^¥	29 ± 0.1	29 ± 0.2^##
B. ogadensis + T. schimper (1:1 ratio)	5	11 ± 0.6	11 ± 0.3	9 ± 0.1	10 ± 0.1	12 ± 0.4	12 ± 0.4
	10	14 ± 0.3	15 ± 0.7	13 ± 0.8	13 ± 0.8	15 ± 0.6	16 ± 0.6
	15	16 ± 0.4	16 ± 0.1	15 ± 0.5	14 ± 0.4	19 ± 0.7	20 ± 0.7
	20	19 ± 0.1	19 ± 0.8	17 ± 0.7	21 ± 0.3	21 ± 0.2	20 ± 0.7
Modern drug		24 ± 0.8	11 ± 1.3(R)	22 ± 0.4	17 ± 0.4(R)	23 ± 0.7	17 ± 0.2(R)

The values represent mean ± standard deviation, N NO inhibition zone, R Resistant (≤16 mm IZ), S=Susceptible (≥ 21 mm IZ). Where, ^*P < 0.05, ^**P < 0.01, ^***P < 0.001when compared to cefoxitin treated MRSA. While, ^#P < 0.05, ^##P < 0.01when compared to modern drug treated K. pneumoniae and ^¥ P < 0.05, ^¥¥P < 0.01 when compared to modern drug treated E. coli

ISSN: 2662-7671