FIG 3.

Cytotoxicity levels of the tested caffeine and maslinic acid against Acanthamoeba (IC₅₀ and IC₉₀) were evaluated against two cell lines: HeLa and murine macrophages. Values lower than 10% correspond to a null cytotoxicity, so the results showed that caffeine IC₅₀ (C50), caffeine IC₉₀ (C90), and maslinic acid IC₅₀ (M50) were not cytotoxic. Values between 10% to 25% correspond to a low cytotoxicity, which was the case for maslinic acid IC₉₀ (M90). Statistical differences between cytotoxicity of the assayed drugs and that produced by the reference drugs chlorhexidine IC₉₀ (Chx90) and amphotericin B (Anf90) were observed in both cell lines (***, P < 0.001).