Volatile Oils of Nepeta tenuifolia (Jing Jie) as an Alternative Medicine against Multidrug-Resistant Pathogenic Microbes

Table 1

Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and MBC/MIC ratios of Nepeta tenuifolia extract (%).

Strain designation	MIC (%)	MBC (%)	MBC/MIC	Amp MIC (g/ml)	Amp MBC (g/ml)
Gram-positive bacteria
Bacillus cereus (BCRC 10603)	0.195	0.260	1.333	128	128
Listeria monocytogenes (BCRC 14846)	0.390	1.170	3.000	0.06	0.06
Staphylococcus aureus subsp. aureus (BCRC 12657)	0.780	2.350	3.013	0.06	0.12
Staphylococcus aureus subsp. aureus (ATCC 29213)	0.780	1.560	2.000	0.12	0.25
Staphylococcus aureus subsp. aureus (ATCC 25923)	1.560	4.690	3.006	0.06	0.12
Gram-negative bacteria
Citrobacter freundii (BCRC 12291)	0.780	1.040	1.333	32	32
Citrobacter freundii (BCRC 12292)	0.390	0.390	1.000	64	64
Escherichia coli (BCRC 10675)	0.390	0.390	1.000	8	8
Escherichia coli (ATCC 43890)	0.097	0.097	1.000	8	8
Salmonella enterica subsp. enterica (BCRC 10744)	0.081	0.097	1.200	2	2
Salmonella enterica subsp. enterica (BCRC 10747)	0.780	0.780	1.000	4	4
Pseudomonas aeruginosa (ATCC 15692)	12.500	>12.5	NA	>128	>128
Pseudomonas aeruginosa (BCRC 10944)	10.417	12.500	1.200	>128	>128
Pseudomonas aeruginosa (ATCC 9027)	5.210	5.210	1.000	>128	>128
Pseudomonas aeruginosa (ATCC 27853)	0.780	0.780	1.000	>128	>128
Pseudomonas aeruginosa (BCRC 13053)	6.250	8.333	1.333	>128	>128

NA: undetermined because MIC and/or MBC values were under the lower limit of each test range.