In Vitro Antigiardial Activity of Selected Plants From the Indonesian Rain Forest Identified Based on Behavioral Observations of Sumatran Orangutans.

BACKGROUND AND AIMS: This study evaluated in vitro antigiardial activity in 16 Indonesian plants extracted in methanol, methanol-tetrahydrofuran (1:1), and water. These plants exhibiting promising antiparasitic activity were selected on the basis of collected behavioral data and the ability of these plants to decrease parasite load in Sumatran orangutans.

METHODS

Plant extracts of different concentrations (0.15625-10 mg/mL) and metronidazole (100 μg/mL), a standard antigiardial drug, were incubated with 105 trophozoites per milliliter of growth medium in 96-well tissue culture plates under anaerobic conditions for 24 h. Cultures were counted in a hemocytometer using a light microscope and then statistically evaluated.

RESULTS

All tested plants were found to be effective to some extent against Giardia intestinalis trophozoites, with eight of them having never been previously tested for any biological activity nor probably used in ethnomedicine (as far as we know).

CONCLUSION

Our results show that these extracts have potential as an alternative treatment of enteric diseases caused by G. intestinalis and confirm the assumption that orangutans use these plants for self-medication.