[Growth inhibition of Entamoeba histolytica and E. invadens produced by pomegranate root (Punica granatum L.)]

The purpose of the present work has been to evaluate the biological activity of alkaloids and tannins extracted from roots of Punica granatum L. on axenic cultures from Entamoeba histolytica and E. invadens, strains. Initially, the total aqueous extract and later some of its components obtained by thin layer chromatography were tested. These compounds were identified by chromatography as alkaloids or tannins. The density of amebic cultures was determined with a hemocytometer after 48 and 96 hours of incubation, which was calculated by the difference between number of trophozoites obtained at the times chosen and the number of amoebae inoculated. Two milliliters of aqueous extract had higher activity on cultures from E. histolytica than E. invadens strains, producing growth inhibitions of about 100 and 40 per cent respectively. Alkaloid concentrations of 1 mg/ml had no amebicide activity, however tannins at concentrations of 10 micrograms/ml for E. histolytica, and 100 micrograms/ml for E. invadens were sufficient to produce an growth inhibition about 100 per cent. Tannic acid was also tested on the cultures of E. histolytica observing an high inhibitory activity on the growth, this effect was produced at 0.01 mg/ml was similar to that observed with the tannins mixture.