Carica papaya family Caricaceacae is one of the herbal remedies, which has recently become a subject of research focus. It is used in traditional medicine for variety of purposes in treating infectious and noninfectious diseases.
The objective of this study was to assess the antibacterial effect of papaya seed extract against bacterial pathogens isolated from wound, urine and stool.
This analytical experimental study was conducted in Jimma University, School of Medical Laboratory Technology, Microbiology laboratory between February to March 2005. The antibacterial activity of methanol extract of papaya seed was investigated against specific pathogenic bacteria isolated from wound, urine and stool by an agar dilution technique and the crude preparation was assessed by an agar diffusion technique. The growth or inhibition of control strains of Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa as well as the clinical isolates of these bacteria were determined in growth media.
Results obtained in this study indicate that the minimum inhibitory concentration of papaya seed extract for 50% of the test bacteria was 18.38mg/ml and for S. typhi the MIC was at 11.8 mg/ml of extract. However, the growth inhibitory effect of papaya seed extract was not observed for P. aeruginosa up to 26.25 mg /ml of extract. Even though, the minimum bactericidal concentration is higher than the minimum inhibitory concentration of papaya seed extract (13.13 mg/ml, 11.8 mg/ml respectively) against S. typhi control and clinical isolates, the minimum bactericidal concentration for 50% of the tested bacteria was found to be similar with the minimum inhibitory concentration of the test bacteria,
Papaya seed could be used as an effective antibacterial agent for the tested organisms. Nevertheless, preclinical studies including invivo animal models and clinical trial on the effect of the seed are essential before advocating large-scale therapy.