Pathogenic Acanthamoeba strains are causative agents of Granulomatous Amoebic Encephalitis (GAE) and Acanthamoeba keratitis (AK) worldwide. The existence of the cyst stage complicates Acanthamoeba therapy as it is highly resistant to antibiotics and physical agents. The aim of this study was to investigate the activity of Limouni olive leaf cultivar against the trophozoite stage of Acanthamoeba. The ethyl acetate and methanol extracts of this variety were tested against Acanthamoeba castellanii Neff. The ethyl acetate extract of olive leaf was the most active showing an IC50 of 5.11±0.71μg/ml of dry extract. Bio-guided fractionation of this extract was conducted and led to the identification of three active compounds namely oleanolic and maslinic acids and oleuropein which could be used for the development of novel therapeutic approaches against Acanthamoeba infections.
Bibliographical noteFunding Information:
This work was supported by the Grants RICET (Project No. RD12/0018/0012 of the programme of Redes Temáticas de Investigación Cooperativa, FIS), Spanish Ministry of Health , Madrid, Spain and the Project FIS PI10/01298 “Protozoosis emergentes poramebas de vida libre: aislamiento y caracterización molecular, identificación de cepas transportadoras de otros agentes patógenos y búsqueda de quimioterapias efectivas” and PI13/00490 “Protozoosis Emergentes por Amebas de Vida Libre: Aislamiento, Caracterización, Nuevas Aproximaciones Terapéuticas y Traslación Clínica de los Resultados” from the Instituto de Salud Carlos III , and was supported by the FP7-REGPOT-2012-CT2012-316137-IMBRAIN project.
I.S. was funded by an alternating Scholarship from the University of Carthage , Tunisian Ministry of Higher Education and Scientific Research and by CEI Canarias , Campus Atlántico Internacional . A.L.A. was funded by a Grant “Ayudas del Programa de Formación de Personal Investigador, para la realización de Tesis Doctorales” from the Agencia Canaria de Investigación , Innovación y Sociedad de la Información from the Canary Islands Government . J.C.T. was supported by a MAE-AECI fellowship. C.M.M.N. was supported by a postdoctoral Grant from the Fundación Canaria Manuel Morales, La Palma, Canary Islands . M.R.B. was funded by CEI Canarias, Campus Atlántico Internacional and Becas FundaciónCaja canarias para Postgraduados 2014 . J.L.M. was supported by the Ramón y Cajal Subprogramme from the Spanish Ministry of Economy and Competivity RYC-2011-08863.
© 2014 Elsevier Inc.
- Bioassay fractionation
- Olive leaf extract