Effect of Oregano and Marjoram Essential Oils on the Physical and Antimicrobial Properties of Chitosan Based Systems

Table 6

Antimicrobial activity of the oregano and marjoram essential oils against selected microorganisms.

Microorganism	Inhibition zone diameter (mm)
	Oregano oil	Marjoram oil
Staphylococcus aureus	26.0 ± 3.0	9.0 ± 1.0
Bacillus cereus	18.5 ± 1.3	26.0 ± 2.3
Salmonella typhimurium	33.5 ± 0.7	25.5 ± 0.7
Escherichia coli	28.0 ± 3.0	14.0 ± 1.0
Candida albicans	43.0 ± 1.0	21.0 ± 1.0
Aspergillus niger	51.5 ± 0.7	x

Values are expressed as mean ± standard deviation; x: no inhibition zone.