Hamadan University of Medical Sciences Avicenna Journal of Clinical Microbiology and Infection 2383-0298 10 4 2023 12 29 In Vitro Evaluation of the Effects of Pelargonium quercetorum Agnew Extracts on Trichomonas vaginalis 157 161 10.34172/ajcmi.3455 EN Ali Azimi Kohan https://orcid.org/0000-0002-5892-7963 Dara Dastan https://orcid.org/0000-0002-7208-208X Mohammad Fallah https://orcid.org/0000-0003-1759-7387 Mohammad Matini https://orcid.org/0000-0002-1098-6382 Journal Article 10.34172/ajcmi.3455 2023 04 30 2023 12 24 Background: Trichomonas infection is a common sexually transmitted infection, and concerns about drug resistance to this infection are increasing. The aim of this study was to evaluate the in vitro activity of Pelargonium quercetorum extracts on Trichomonas protozoans. Methods: One isolate of Trichomonas vaginalis was subjected to susceptibility testing against ethyl acetate, n-hexane, and aqueous extracts of P. quercetorum using the microtiter plate method. The minimum lethal concentration (MLC) of the extracts was measured in comparison with metronidazole under aerobic conditions. Results: All extracts had antiprotozoal activities against Trichomonas. After 48-hour exposure, the most antitrichomonal activity of the extracts belonged to the ethyl acetate, with an MLC of 250 µg/mL, followed by the n-hexane (500 µg/mL) and aqueous (25 mg/mL) extracts in comparison with metronidazole, with an MLC of 3.1 µg/mL. Conclusion: The results of this study indicated that P. quercetorum has potential properties against Trichomonas protozoans, although further studies are needed to evaluate the antiprotozoal activity of its components.