RT Journal Article T1 Antiprotozoal Potential of Cultivated Geranium macrorrhizum Against Giardia duodenalis, Trichomonas gallinae and Leishmania infantum A1 Marcos-Herraiz, Sara A1 Irisarri-Gutiérrez, María José A1 Carrión Herrero, Francisco Javier A1 Azami Conesa, Iris A1 Suárez Lombao, Rodrigo A1 Navarro-Rocha, Juliana A1 Quilez del Moral, Jose Francisco A1 Fernández Barrero, Alejandro A1 Ochoa Larrigan, Eneko A1 González-Coloma, Azucena A1 Gómez Muñoz, María Teresa A1 Bailén, María AB Plant-derived natural products are an invaluable source of structurally diverse secondary metabolites with ecological and pharmacological significance. Geranium macrorrhizum, a species known for producing essential oils rich in monoterpenoids and sesquiterpenes, has been scarcely explored for its antiparasitic potential. This study represents the first comprehensive evaluation of the antiprotozoal activity of G. macrorrhizum obtained from cultivated plants. Plant material was produced under controlled greenhouse cultivation systems, ensuring high-quality and reproducible metabolite profiles. Essential oils were obtained through hydrodistillation and chemically characterized by Gas Chromatography-Mass Spectrometry (GC-MS). In vitro assays were conducted against Giardia duodenalis, Trichomonas gallinae, and Leishmania infantum to assess antiparasitic efficacy and cytotoxicity. The results demonstrated strong activity of essential oils against Trichomonas gallinae, and Leishmania infantum, indicating the relevance of lipophilic compounds-especially germacrone-as key bioactive constituents. Germacrone exhibited strong and selective antiparasitic activity, outperforming its structural analogues. Microscopic analyses revealed distinct parasite-specific morphological alterations, differing from those induced by conventional drugs such as metronidazole and amphotericin B. These findings highlight G. macrorrhizum obtained through biotechnological cultivation as a novel and sustainable source of natural antiprotozoal agents. The study underscores the importance of integrating controlled cultivation with phytochemical and biological evaluation to advance the discovery of innovative bioactive compounds. PB MDPI SN 1661-6596 YR 2026 FD 2026 LK https://hdl.handle.net/20.500.14352/132196 UL https://hdl.handle.net/20.500.14352/132196 LA eng NO Marcos-Herraiz, S., Irisarri-Gutiérrez, M. J., Carrión, J., Azami Conesa, I., Suárez Lombao, R., Navarro-Rocha, J., Del Moral, J. F. Q., Fernández Barrero, A., Ochoa Larrigan, E., González-Coloma, A., Gómez-Muñoz, M. T., & Bailén, M. (2026). Antiprotozoal Potential of Cultivated Geranium macrorrhizum Against Giardia duodenalis, Trichomonas gallinae and Leishmania infantum. International journal of molecular sciences, 27(2), 1125. https://doi.org/10.3390/ijms27021125 NO Author Contributions: Conceptualization, A.G.-C., M.T.G.-M. and M.B. Data curation, A.G.-C., M.T.G.-M. and M.B. Formal analysis, S.M.-H., M.T.G.-M., M.J.I.-G., J.C., A.G.-C. and M.B. Funding acquisition, A.G.-C. and M.T.G.-M. Investigation S.M.-H., M.J.I.-G., I.A.C., R.S.L. and J.C. Methodol ogy, A.F.B., E.O.L., J.F.Q.d.M., J.N.-R., M.J.I.-G., J.C., A.G.-C., M.T.G.-M. and M.B. Resources, A.G.-C., J.N.-R., A.F.B., E.O.L., J.F.Q.d.M., J.C., M.T.G.-M. and M.B. Supervision: A.G.-C., M.B. and M.T.G.-M. Writing—original draft, M.T.G.-M. and M.B. Writing, reviewing and editing, A.G.-C., M.T.G.-M. and M.B. All authors have read and agreed to the published version of the manuscript NO Ministerio de Ciencia, Innovación y Universidades (España) NO State Research Agency DS Docta Complutense RD 17 mar 2026