Internet Journal of Food Safety V (7): 15-19 Antibacterial Activity of Essential oil from Ocimum gratissimum on

The antibacterial effect of Ocimum gratissimum extracted from aromatic plant was investigated against Listeria monocytogenes serotype 4a. Agar well diffusion and tube dilution methods were used and the data recorded demonstrated antibacterial activity of the essential oil Eos against the test bacteria. The bacteria was grown at 370C in a chemically defined or a complex medium, containing essential oil obtained from Ocimum gratissimum. At concentration from 20 to 250µg/ml, the essential oil, progressively inhibited the bacterial growth. The bacteria cultivated on chemically defined medium were more sensitive to essential oil at concentration of 50, 62.5 and 100µg/ml in relation to those cultivated in complex medium at 370C. The agar well diffusion was also evaluated. The results yield a zone of inhibition of 25mm. These established a good support to the use of this plant in herbal medicine and as base for the development of new drugs and phytomedicine