Introduction: Today, the use of medicinal plants with the aim of improving respiratory problems, treating infections, reducing the side effects of synthetic-chemical compounds and bacterial resistance to antibiotics has become very important. Passionflower (Passiflora caerulea L.) is a valuable medicinal plant and has potential antibacterial compounds. The phenolic compounds present in Passiflora caerulea have a very important role in inhibiting the growth of bacteria. These compounds are a good alternative to chemical antimicrobial compounds. The present study was conducted with the aim of comparing the antimicrobial effects of the extracts of the leaves and stems of the P. caerulea against human pathogens. Methods: The antibacterial properties of the leaf and stem extracts of the P. caerulea was tested against four human pathogenic bacteria, Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Streptococcus pyogenes, by broth microdilution method. Minimum Inhibitory concentration (MIC) and Minimum Bactericidal concentration (MBC) were measured to evaluate the antibacterial effects of P. Caerulea extracts. Results: The analyzed results showed that the ethanol extract of the leaf compared to the stem extract has the highest growth inhibition rate against the tested bacterial species. Conclusion: Therefore, the results of the study can help as a new strategy for the development of new drugs against pathogenic microbes and progress in the future of the pharmaceutical industry.
