ANTIMICROBIAL ACTIVITIES OF SCENT LEAVES (OCIMUM GRATISSIMUM) ON ESCHERICHIACOLI AND SALMONELLATYPHI

Abstract

Essential oils or volatile oils from medicinal plants have potentially very strong anti microbial activities for the control of pathogenic micro organisms. Ocimum gratissimum is one of the medicinal plants which are widely used as sources of extracts with strong antibacterial and anti oxidant properties. In this study the leaf extract of Ocimum gratissimum was tested for its antibacterial activity against some human pathogenic bacteria (salmonella typhi and Escherichia coli). Antibacterial activity test was carried out by using the agar plate diffusion method. The plants materials were dried and extracted with 90% ethanol and water. The tested extract exhibited a significant antimicrobial activity against both strains. The antimicrobial activity was determined by measuring the zones of inhibition. The most significant inhibitory activity was observed against E. coli (22mm zone and 18mm zone) at 100mg/ml for both ethanolic and aqueous extracts. The physical properties of the extracts of Ocimum gratissimum were evaluated. The colours of the extracts were greenish and brownish for ethanol and aqueous extracts respectively. Phytochemical properties of the plants were analysed and the plant was confirmed to contain alkaloids, cyanide, flavonoids, saponis, carbohydrates, tannins, oxalates and phytates.