Background: Giardia lamblia
is a parasite that causes giardiasis in humans and other mammals. The common treatment includes different drugs,
which were described to produce unpleasant side effects. Citrus aurantifolia
, popularly known as “lima”, is a plant used in traditional medicine to treat
gastrointestinal symptoms. The aim of the present study was to evaluate the anti-Giardia activity of 10 pure compounds obtained from a hexanic
extract of Mexican lime on the basis of trophozoite growth inhibition.
Materials and Methods:
A hexanic extract obtained from fresh fruit peels of Citrus aurantifolia
was tested on G. lamblia
trophozoites cultured in TYI-S-33 medium. The concentration of all standard drugs, analyzed by gas chromatography, was adjusted at 10 mg/mL.
Metronidazole was used as a positive control. Growth inhibition was determined by counting the number of trophozoites using a Neubauer chamber.
The 50% inhibitory concentration (IC50
) of each drug was calculated by probit analysis and 95% confidence limits were calculated.
4-hexen-3-one, citral and geraniol showed IC50
values of 34.2, 64.5 and 229.49 μg/ml in axenic cultures after 24 hr of incubation,
respectively. When these results were compared with a positive control of metronidazole; 4-hexen-3-one was 66 times; citral was 112 and geraniol
was 441 times less active respectively. The other tested compounds did not inhibit the growth of cultured G. lamblia
The obtained results lead us to propose that these tested compounds from C. aurantifolia
have potential for use as therapeutic agents