Antibacterial Activity of Leaves and Stem Extract of Carica papaya L.

It was reported that the extracts of papaya leaves could inhibit the growth of some bacterial pathogens. Antibacterial activity of Carica papaya leaf extracts on pathogenic bacteria was observed in this study. Papaya leaves were extracted by using maceration method and three kinds of solvents: ethanol and ethyl acetate. Papaya leaf and stem extracts were tested against both Gram positive and Gram Negative bacteria such as Staphylococcus aureus, Streptococcus pneumonia, Bacillus cereus, Salmonella typhi, Escherichia coli and Pseudomonas aeroginosa by diffusion method. The extract demonstrated higher activities against all the Gram negative bacteria than Gram positive bacteria tested, with the highest activity (16 mm zone of inhibition) demonstrated against Salmonella typhi. Increase in temperature enhanced the activity of the extracts, while alkaline pH decreased the activity. The Minimum Inhibitory Concentration (MIC) of the extracts ranged between 50-200 mg/ml. Preliminary phytochemical analyses showed that the extracts contain alkaloids, tannins, saponins and phenols. Carica papaya may be used for the treatment of gastroenteritis, uretritis, otitis media, typhoid fever and wound infections.