In vitro Tests for Efficacy of Tannins Extracted from Pomegranate (Punica granatum) Against Schistosoma mansoni Miracidia

The objective of the present study was planned to i nvestigate the in vitro efficancy of Punica granatum tannins of stem and root bark and fruit rind and p lacenta on miracidia of Schistosoma mansoni using different serial double concentrations. Resu lts showed that a concentration as low as 0.39 ppm o f the investigated tannins was enough to kill 100% of miracidia after 50-150 min and to kill 50% of miracidia within 25.1-48.3 min. At 50 ppm, the lethal time for 100% of miracidia ra nged between 5 and 15 min and the lethal time for 50% miracidia ranged between 0.5 an d 6 min. Placenta tannins were the most potent biocide for miracidia amongst the four tannins of pomegranate (P ≤ 0.05). Fifty ppm pomegranate root and stem bark tannins killed 100% miracidia after 0.6 and 50 min, respectively, and 0.39 ppm killed 50% miracidia aft er 0.6 and 21.6 min respectively. The results concluded that the four investigated tannin s of P. granatum were found to be completely lethal to Schistosoma mansoni miracidia and can be used as biocide.