journal article·2025-04-10Open access

Melaleuca alternifolia Cheel (Tea Tree) and Eucalyptus globulus Labill. Essential Oils’ Effectiveness Against an Acanthamoeba polyphaga Strain Responsible for Human Keratitis

Ramona Iseppi, Martina Mariani, Carla Sabia, Patrizia Messi

Applied Sciences· Volume 15· Issue 8

Abstract

Among free-living amoebae (FLA), Acanthamoeba polyphaga is an important causal agent of Acanthamoeba keratitis (AK), a severe and potentially sight-threatening condition. The present study evaluated the “in vitro” efficiency of Melaleuca alternifolia Cheel (tea tree) (tea tree oil—TTO) and Eucalyptus globulus Labill. (Eucalyptus essential oil—EEO) essential oils against an Acanthamoeba strain isolated from human keratitis. The Minimum Inhibitory Concentration (MIC) of the EOs and the Fractional Inhibitory Concentration (FIC) Index were used to evaluate the decrease in viable cells of Acanthamoeba over time and at different concentrations of EOs, used alone or in association. A relevant amoebicidal effect emerged during the first hours of exposure for both compounds, and TTO was the most effective. The TTO/EEO association clearly indicated a synergistic effect in all tests, and at 2 days post-treatment, no viable A. polyphaga cells were observed at all tested concentrations. In conclusion, the potential therapeutic use of EOs represents a promising therapeutic strategy for the treatment of AK.
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Research context

OpenAlex topics: Essential Oils and Antimicrobial Activity · Phytochemistry and biological activity of medicinal plants · Phytochemistry and Biological Activities

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Life Sciences, University of Modena and Reggio Emilia, Via G. Campi 287, 41125 Modena, Italy

Burn Intensive Care Unit, Hospital A. Cardarelli, Via A. Cardarelli 9, 80131 Naples, Italy

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