Amoebicidal and Cytotoxic Activity of Propolis collected from Different Regions in Turkey on Acanthamoeba castellanii Trophozoites

Abstract

Objective: The present study aimed to investigate the amoebicidal effects of propolis collected from different regions in Turkey on Acanthamoeba trophozoites. Method: The propolis was collected from different geographic sites (Van, Erzurum, Gümüşhane, Ordu, Rize, and Muğla) in Turkey. Different concentrations of propolis ethanolic extract (in quantities from 1, 2, 3, 4, 5, 6, 7, and 8 mg/mL) and the same volume of trophozoites in 100 μl culture were blended for the identification of the amoebicidal efficiency of propolis. Results: The growth of trophozoites stopped in Turkish propolis extracts with 50% inhibitory concentrations (IC50)/48h for 5 mg/mL extract solution. Propolis showed more potent inhibitory effects on Acanthamoeba trophozoites at concentrations of 7, 6, 5, 4, and 3 mg/mL for 72 h. Propolis extract substantially inhibited human bronchial epithelial cells, especially at higher concentrations (7, 8, and 16 mg/mL). Propolis can kill Acanthamoeba trophozoites at a concentration (of 3-6 mg/mL) but is safe for human bronchial epithelial cells at the same concentrations after 72 h treatment, this paves the way for propolis to be an alternative source of therapeutic drugs in the treatment of Acanthamoeba spp. Conclusion: Acanthamoeba infection still cannot be treated with drugs. In this study, propolis collected from different regions of Turkey showed amoebic and cytotoxic activities. Propolis extract, which is a natural product that can be used against Acanthamoeba trophozoites can be an alternative source of therapeutic drugs in the treatment of Acanthamoeba, supported by in vivo studies.