First Report on the in vitro Antihelminthic Activity of Centella Asiatica (“Gotu Kola”/ “Vallaarai”)

Abstract

Anthelmintic resistancehas been reported in animals and also suggested in humans. Thus, there is an urgent need for the identification and development of alternative anthelmintics for human use. With this background, a study was designed to examine two medicinal plants, Vernonia anthelminthica and Punica granatum, having known antihelmintic activity with another herbal plant, Centella asiatica. The aqueous, ethanol and methanol extracts of fresh roots, seeds and leaves of the above plants were obtained separately. Anthelmintic activity was tested in vitro by using the earth worm (Eisenia fetida)as described earlier. The worms were placed in separate Petri dishes containing 30ml suspensions of methanol, ethanol and aqueous extracts (25mg/ml and 50 mg/ml) of plant extracts. Albendazole at 20 mg/ml and 1% acacia in normal saline were used as the reference standard and the control group respectively.Time taken for complete paralysis and death of individual worms was recorded. All three crude extracts of plants showed greater anthelmintic activity than that of albendazole. The solution containing 50mg/ml aqueous extract of Vernonia anthelminthica seeds paralyzed the earth worm within the shortest time (5.10±0.14 min) followed by the solution containing 50mg/ml ethanolic extract of Centella asiatica leaves (7.09±0.12 min). Though antihelmintic activity of crude extract was increased proportionately with increased dose, all three plants showed optimum antihelmintic activity at 50mg/ml, promoting paralysis and subsequent death of the worms. It can thus be concluded that in addition to other nutritional values such as iron and folic acid, this is the first report of the antihelmitic activity of Centella asiatica